Topic/reqs 298

* Demo tests are in **SingleNameCDSE2ETest** and **CDSIndexE2ETest**.
* IR01, JTD and recovery01 calculations are added to **CDSIndexCalculator**. 
rewrite this as 
double w = intrinsicData.getWeight(singleName);
 double protection = intrinsicData.getLGD(singleName) ;
double singleNamePV = _pricer.pv(indexCDS, yieldCurve, intrinsicData.getCreditCurves()[singleName], indexCoupon);
return w*(protection - singleNamePV);