Removed long-deprecated Matrix2 and Matrix2d typedefs.
Removed long-deprecated Matrix2 and Matrix2d typedefs.

Use Matrix2x2 and Matrix2x2d instead.

DerThorsten/magnum,DerThorsten/magnum,ashimidashajia/magnum,MiUishadow/magnum,MiUishadow/magnum,MiUishadow/magnum,ashimidashajia/magnum,DerThorsten/magnum,ashimidashajia/magnum,MiUishadow/magnum,MiUishadow/magnum,MiUishadow/magnum,DerThorsten/magnum,ashimidashajia/magnum,DerThorsten/magnum,ashimidashajia/magnum