* also removed it from haiku1-config.py CPPDEFINES
(it's place is in user-config.py if present)
* removed unneeded code (already commented) for spawning of
the BApplication Run()ing thread
* No functional changes over the initial one
* Explicitely use python2.5 as builds with python2.6 show issues on launching the
resulting blender binary (no time to investigate, yet)