Fixing 2d rendering; all renderers.
New convention: cam3D doesn't take into account scaling, while cam2D
does. Ramains to fix GeomFrame API and deal with iDrivable frame (deal
when it actually is a cam3D) and iAvatar
Scl API first attempt: adding noScl option in GeomFrame transformations.
Fixes everything, including pixelP5Ratio and alignWithFrame. FrustumEqns
work without any modification. DrawCamera and drawWindow have been fixed
in Renderer* classes as well.