Changelog dev

This file is used to accumulate changes before a changelog for a release is created.

Added new method update_bbox to BBMOD_Mesh.
Methods from_buffer and to_buffer of BBMOD_Mesh now throw a BBMOD_Exception if used when property Model is undefined. Previously this would cause a crash.
Fix ClearColor of BBMOD_DeferredRender resulting into a wrong color because of gamma correction.