Move pc.gfx API to the top level pc namespace. Everything remains backwards compatible.
Merge branch 'master' into feature/remove-gfx-namespace
Upgraded the rest of the engine to use the global namespace for graphics objects.
Remove pc.programlib namespace from appearing in the docs.
Merge pull request #131 from playcanvas/feature/remove-gfx-namespace

Move pc.gfx API into the top level pc namespace.