Refactor Legendre (#303)
Refactor Legendre (#303)

* Legendre refactoring for static size

* Migrate from std::vector to std::array to enable static optimization.

* Make table lookup optional
mlund/faunus,mlund/faunus,bjornstenqvist/faunus,bjornstenqvist/faunus,mlund/faunus,bjornstenqvist/faunus