Update to last changes in Blender
Fix use 'yaf_use_alpha' value from last commit

This changes only working in Blender belong rev 53.703
Update 'template_list' code to Blender 2.66 changes.
Add flags for compatibility with preview versions.
Update code  for 'template_list' changes in Blender 2.66.
Starting some task for show only YafaRay useful options in texture panels.
Created new option for 'use_alpha' because Blender 2.66 has changed the context of this variable.
Hidden some options in texture world panels, not used by YafaRay
Deleted try: except: ATM, this method seems is not need.
-After more test, this part working fine without errors.
This code is was update for me, very time ago with the first versions
of YafaRay integration in Blender 2.5 in not more stable state.

-Added texture projection options to "world panel" for improve it the work flow
Reverse this commit, if is 'source' of users errors.
-Disable "gamma_encode" and "clamp_rgb" options for sunsky2, changed int the last fix of DarkTide.
Add "area light" size control panels for fix issue to "negative scale" values in area light geometry.
Update code for 'template_list' to Blender 2.66 version.
Add flags for compatibility and old versions
Add  more explicit comment to 'Create geometry' in  "area light" panel
Create new property "yaf_mapworld_type" for YafaRay texture background modes.
Create YafaRay texture background mapping modes
Add own YafaRay texture background mapping modes.
Update style code and use Python dict format,
more efficient and more flexibility.
Changed reserve Python built-in symbol 'dir' used in 'sun' direction vector
Merge pull request #11 from povmaniaco/master

Update exporter to Blender 2.66a