initial: implemented prototype of enum option. added option_structure.h for global constants and enums

merge origin into feature_quadrature, nothing special

changed psi structure, added derivatives and sources

See merge request !1

added generic lookup-quadrature. added ldfesa quadrature. Changes to access specifiers for quadrature classes.

Added code comments and some override specifiers for better readbility. Added inline specifiers for less function overhead

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