[Bf-python] __blender__ constant

[dunk]

hi, 

it would be nice to be able to detect when a script/module is being run inside 
blender or not. perhaps the existence of a __blender__ variable would help 
here? im not entirely sure what the variable would contain... maybe the 
blender version?

the only other way i can think to detect if blender is around is using a 
try/except around import Blender but this doesnt "feel" quite right. 
of course even using a variable would still mean the same try/except but it 
would read nicer:
try:
	__blender__
except NameError:
	# no blender

dunk