- VBO_CONTAINER::allocate() was returning wrong value in case of error
- framelimiter had wrong formula for computing destined period between frames
- removed _padding field from VBO_VERTEX, as it was not speeding up, but wasting memory
Removed a few unnecessary variables and fields from OPENGL_GAL.
Added function GAL::ClearCache() for freeing memory used by cached items.
Fixed a few memory leaks (tesselator, PAINTER's settings & VIEW_ITEM's groups).
Changed a few functions into inlines.