PATENTS ACT, 1970 (39 of 1970) COMPLETE SPECIFICATION (See Section 10) The following specification particularly describes the nature of the invention and the manner in which it is to be performed. The present invention relates to a particulate laundry detergent composition, which may for example be formulated as a particulate or tablet composition. BACKGROUND TO THE INVENTION Conventional laundry detergent powders intended for the handwash contain a substantial level of anionic surfactant, most usually alkylbenzene sulphonate. Anionic surfactants are ideally suited to the handwash because they combine excellent detergency on a wide range of soils with high foaming. However, event at high levels of anionic surfactant, for handwashing, the oily soil removal performance of such products is in need of improvement. GB-A-1 570 128 discloses detergent compositions comprising from 4 to 40 wt% of a magnesium-insensitive surfactant (for example, alkyl sodium silicate, and from 5 to 50 wt% of a magnesium-selective detergency builder (for example, zeolite, ether sulphate, ethoxylated nonionic surfactant, amine oxide), from 13 to 40 wt% of sodium citrate, nitrilotriacetate, or calcite/carbonate). JP-A-09 087 690 discloses a high-buik-density granular detergent composition for machine wash use, containing anionic (5 to 40 wt%), plus ethoxylated nonionic surfactant (1 to 15 wt%), zeolite {10 to 40 wt%), and crystalline and amorphous sodium silicates (0.5 to 10 wt%). The anionic surfactant optionally contians alpha-olefin sulphonate (up to 10 wt% in the examples). WO-A-97/43366 relates to detergent composition comprising from 0.5% to 60% by weight an anionic surfactant and from 0.01% to 30% by weight of a cationic surfactant. In the exemplified compositions in this document, the level of anionic surfactant is typically from about 10% to 15% by weight of the composition and the amount of cationic surfactant is from about 1% to 4% by weight. In some examples, the anionic surfactant component contains small amounts of an alkyl ether sulphate surfactant, typically at from 0.76% to 2.5% by weight of the total composition. Compositions with small amounts of alkyl ether sulphate anionic surfactant (up to -1.75 wt%) and in one case, a low amount of zeolite (1.5 wt%) are disclosed in WO-A-98/01521). However, these compositions are spray-dried and therefore have high amounts of sodium sulphate which is a non-alkaline non-functional water-soluble salt (electrolyte). Other spray-dried compositions with high levels of sodium sulphate and containing alpha-olefin sulphate anionic surfactant, together with 12 or 15 wt% zeolite builder are disclosed in JP-A-62 218499. WO-A-00/40682 discloses compositions comprising more than 40% of an anionic surfactant system at least some comprising a calcium tolerant surfactant such as an alpha-olefin sulphonate or alkyl ether sulphate. The examples with calcium tolerant surfactant either contain no phosphate or aluminosilicate builder or else a very high level of phosphate. WO-A-01/21757 also discloses compositions with 5-30 wt% of alpha-olefin sulphonate. These are all based on a calcite /carbonate builder system. Other compositions containing calcium tolerant surfactants are disclosed in US-A-6 010 996, GB-A-2 309 706, US-A-5 415 812, US-A-4 265 777 and US-A-4 970 017. The present invention now solves the problem of improving oily/greasy soil removal, especially at low dosages and/or under hard water conditions. 3 DEFINITION OF THE INVENTION A particulate detergent comprising (a) more than 40% by weight to 95% by weight of anionic surfactant; (b) from 0.1% to 10%, preferably from 0.5% to 5% by weight of cationic surfactant; and (c) the balance being other components; said composition comprising from 35% to 95%, preferably from 45% to 95%, more preferably from 55% to 95% by weight of the total composition of a calcium-tolerant anionic surfactant comprising alpha-olefin sulphonate and alkyl ether sulphate. DETAILED DESCRIPTION OF THE INVENTION The composition of the invention is based on mixed calcium tolerant anionic surfactant systems, plus moderate amounts of phosphate and./or aluminosilicate builder. The anionic surfactant system The composition of the invention contains from more than 40wt% to 95wt% of anionic surfactant. Typically, the upper level of this anionic surfactant will be 75wt%. However, preferably, the anionic surfactant is present at from 45wt% to 65wt%, more preferably from 45wt% to 60wt%, based on the weight of the total composition. Preferably the anionic surfactant (which may be a mixture of anionic surfactants), comprises from 1 % to 100% by weight of calcium tolerant surfactant. 4 The calcium ion stability of anionic surfactants can be measured by the modified Hart method (Witkes, et at. J. Ind. End. Chem. 29, 1234-1239 (1937)), carried in microtiter plates. The surfactant solution is titrated with a calcium ion solution. The onset of turbidity indicates the start of formation of insoluble calcium precipitates after a minute of shaking at room temperature. As referred to herein, a "calcium tolerant" surfactant is one that does not precipitate at a surfactant concentration of 0.4 g/L (and a ionic strength of a 0.040 M 1:1 salt solution at) with a calcium concentration up to 20° FH {French hardness degrees), i.e. 200 ppm calcium. The preferred non-soap calcium tolerant anionic surfactant for use in the compositions of the present invention is alpha-olefin sulphonate. Advantageously alkyl ether sulphate (another non-soap calcium tolerant material) is present, preferably as a co-surfactant with the alpha-olefin sulphonate, in an amount less than that of the latter. A preferred surfactant system comprises alpha-olefin sulphonate and alkyl ether sulphate in a weight ratio of from 5:1 to 15:1. Other calcium-tolerant anionic surfactants that may be used in combination with these or other calcium-tolerant anionics are alkyl ethoxy carboxylate surfactants (for example, Neodox (Trade Mark) ex Shell), fatty acid ester sulphonates (for example, FAES MC-48 and ML-40 ex Stepan), alkyl xylene sulphonates, dialky) sulphosuccinates, fatty acid ester sulphonates, alkyl amide sulphates, sorpholipids, alkyl glycoside sulphates and alkali metal (e.g. sodium) salts or saturated or unsaturated fatty acids. More than one other anionic surfactans may also be present. These may for example be selected from one or more of alkylbenzene sulphonates, primary and secondary alkyl sulphates. 5 When it is desired to avoid the calcium intolerance of alkylbenzene sulphonate surfactant altogether, then the anionic surfactant system may comprise (preferably at a level of 70 wt% or more of the total anionic surfactant) or consist only of ono or !i calcium-tolerant non-soap anionic surfactants. Cationic surfactant systems The compositions of the present invention contain from 0.1 % to 10% by weight of the 10 cationic surfactant system. Typically, the cationic surfactant system may be present at from 0.5 wt% to 5 wt% at the composition. Preferred cationic surfactant types include those having the formula: \S R1R2R3R4N+ X- wherein R1 = is a hydrophobic group (preferably) C12 -14 alkyl, or derived from Coco; R2, R3 or R4 are independently hydroxyethyl, hydroxypropyl or C1-4 alkyl (e.g. Me, ^0 Et) group; X- is a solubilising cation, preferably CI-, Br- or MeS04" Specific examples are: R1 R2, R3, R4 (i) alkyl hydroxyethyl C12 2 methyl, 1 hydroxyethyl dimethylammonium chloride HoeS3996 (now sold as Praepagen HY) (ex Clariant, prev. Hoechst) (ii) Alkyl dihydroxyethyl C12 1 methyl, 2-hydroxyethyl methylammonium chloride Bis-AQA types (ex Clariant) e.g. Ethoquad C/12 type (AKZO-Nobel) (iii) alkyl trimethyf