added getS1HiggsTriCoup, getS2HiggsTriCoup, getS3HiggsTriCoup to NmssmSoftsusy for later use in self energies.
 added NmssmSoftsusy::pis1s2Higgs(double p, double q) and NmssmSoftsusy::pis1s2.  pis1s2 tested against my other verions of nmssm code and against flexi susy and matches. pis2s2Higgs outline added, to be filled next.