* not_ -> not
* equal overload with epsilon -> equal_epsilon
* ortho(l, r, b, t) -> infinite_ortho
* tweaked_infinite_perspective(fovy, aspect, near, ep) -> tweaked_infinite_perspective_ep
* Function overload: the vec version is suffixed by _vec
* Function overload: the methods taking an epsilon as suffixed by _eps
* L1Norm and L2Norm between two vectors have been renamed: l1_distance, l2_distance