Incremental progress toward archive loading in o3d-webgl. Implemented...

Incremental progress toward archive loading in o3d-webgl. Implemented
ArchiveRequest, which expects to be pointed to the top-level scene.json,
and which emulates the behavior of the O3D plugin by downloading the
referenced resources and creating RawData objects for each. Pulled in
public domain JSON parser from http://www.json.org/ . Implemented portions
of TextureCUBE. Fixed some unimplemented functionality and a few bugs
related to creation of parameters. At this point a larger refactoring of
o3d-webgl is needed to make the deserialization work properly, so this code
is being checked in as a checkpoint.

Also fixed small bug in the cg_to_glsl converter script.

BUG=none
TEST=none
TBR=petersont,amarinichev


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=45143