Matrix4 code cleanup
Matrix4 code cleanup

 * Don't assume the values are float, use T(0) instead of 0.0f.
 * Explicitly specify templated type.

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