An engine to use for output can now be selected an influences what
shows in the buttons window, only showing relevant data. The idea
behind this is to make it more clear what is supported where, make
the system more pluggable for external render/game engines, and save
space hiding stuff that is not relevant anyway.
* Top header now has an engine menu, to choose between the blender
render engine, game engine, and other future external engines.
* If the game engine is enabled, the buttons window should show
only properties that work in the game engine, and similarly for
the render engine.
* Moved panels from the logic space and game tabs to the physics,
scene and world tabs instead, and removed the game tab.
* Materials and textures tabs should eventually become game
specific too, to better show what is supported.
Changed order of panels in scene buttons to better follow order of importance, putting the post-processing options further down.
Cleaned up game physics properties
Logic Panel:
- world settings (moved from world)
... that includes physic engine selection + gravity
- game player (from gamesettings, it wasn't wrapped)
- stereo/dome (from gamesettings, it wasn't wrapped)
... separated stereom into stereoflag and stereomode
- properties
... (didn't touch it)
Buttons Game Panel:
(wip panel)
- Physics (moved from Logic Panel)
... it will be a datablock in the future (right Campbell ?)
- Material Physics (not currently implemented)
... a datablock link to the materials of an object + the dynamic physic variables
* NOTE:
in readfile.c::do_version I couldn't do if(scene->world). There is something wrong with scenes with an unlinked world. So so far we are ignoring the old values....
