Improve MathUtils.asin(), acos() (#6332)
Improve MathUtils.asin(), acos() (#6332)

The average and largest error are significantly better for this version (2-3 orders of magnitude), and it can be slightly faster.
cypherdare/libgdx,NathanSweet/libgdx,stinsonga/libgdx,libgdx/libgdx,bladecoder/libgdx,bladecoder/libgdx,tommyettinger/libgdx,tommyettinger/libgdx,bladecoder/libgdx,stinsonga/libgdx,Zomby2D/libgdx,NathanSweet/libgdx,tommyettinger/libgdx,tommyettinger/libgdx,libgdx/libgdx,stinsonga/libgdx,Zomby2D/libgdx,libgdx/libgdx,Zomby2D/libgdx,cypherdare/libgdx,libgdx/libgdx,cypherdare/libgdx,tommyettinger/libgdx,stinsonga/libgdx,bladecoder/libgdx,cypherdare/libgdx,libgdx/libgdx,Zomby2D/libgdx,bladecoder/libgdx,Zomby2D/libgdx,NathanSweet/libgdx,cypherdare/libgdx,NathanSweet/libgdx,NathanSweet/libgdx,stinsonga/libgdx