Removed recrusive/looping legendre functions and used gsl gsl_sf_legendre_Pl_array functions for the m=0 case. Brought back gsl_sf_legendre_Plm_array for gsl v1
Removed recrusive/looping legendre functions and used gsl gsl_sf_legendre_Pl_array functions for the m=0 case. Brought back gsl_sf_legendre_Plm_array for gsl v1

jobovy/galpy,jobovy/galpy,jobovy/galpy,jobovy/galpy