Legendre functions

"Geodesy" 4π normalized
`PlmBar`	Compute all the geodesy-normalized associated Legendre functions.
`PlmBar_d1`	Compute all the geodesy-normalized associated Legendre functions and first derivatives.
`PlBar`	Compute all the geodesy-normalized Legendre polynomials.
`PlBar_d1`	Compute all the geodesy-normalized Legendre Polynomials and first derivatives.
Orthonormalized
`PlmON`	Compute all the orthonormalized associated Legendre functions.
`PlmON_d1`	Compute all the orthonormalized associated Legendre functions and first derivatives.
`PlON`	Compute all the orthonormalized Legendre polynomials.
`PlON_d1`	Compute all the orthonormalized Legendre polynomials and first derivatives.
Schmidt normalized
`PlmSchmidt`	Compute all the Schmidt-normalized associated Legendre functions.
`PlmSchmidt_d1`	Compute all the Schmidt-normalized associated Legendre functions and first derivatives.
`PlSchmidt`	Compute all the Schmidt-normalized Legendre polynomials.
`PlSchmidt_d1`	Compute all the Schmidt-normalized Legendre polynomials and first derivatives.
Unnormalized
`PLegendreA`	Compute all the unnormalized associated Legendre functions.
`PLegendreA_d1`	Compute all the unnormalized associated Legendre functions and first derivatives.
`PLegendre`	Compute all the unnormalized Legendre polynomials.
`PLegendre_d1`	Compute all the unnormalized Legendre polynomials and first derivatives.
Other
`PlmIndex`	Compute the index of an array of Legendre function corresponding to degree L and angular order M.