Blender Git Loki

BPython:
- new submodule Scene.Radio, for radiosity: still incomplete, but in shape for demos, updated SConscript to include it;
- new functions in Window module;
- doc updates: adding a todo file and a new start page for our docs: API_intro.py + other updates;
- small fix in Ipo.c provided by Damien McGuinnes (thanks!): Nathan has a patch with IPO additions and fixes for this and more, but until it is committed, there's this fix for Ipo.getCurve('LocX'), LocY, Z and QuatW,X,Y,Z too, according to Damien.

Other files:
- radpreprocess.c: added check for "during_script()" so eventual msgs don't popup during scripts;
- drawmesh.c: made a pointer (display list) be checked before accessed, fixes crash in scripts that forget to update display lists for subsurf meshes when a 3d view is in textured view mode.

Script: updated bevel_center by Loic Berthe.