Release Name: 0.0.2

Notes:
Librend 0.0.2 "The Great 3x Slowdown"

Added picking, so now you can query objects whether they're
under the mouse cursor or not. It's not perfect by any 
means, but gets the job done in most simple cases (most 
notably, can't pick objects in vector scenes, since that 
requires mapping click to texture coords and I don't know 
how to do that.)

Moved renderer to collect drawables into a list and keep it 
updated on scene changes (the old way was to do a DFS 
through the scene on every frame.) This caused a good deal 
of the inlined bits to become obsolete, which along with the 
addition of the picking rendering pass resulted into a big 
drop in framerate. But it's CPU-bound (or rather, 
Ruby-bound), so rewriting some parts for speed might well 
yield considerable speed-ups. 

In a nutshell: usable but slow.



Changes: