Update README.markdown for IDL bindings.
Rebuild box2d.js with IDL bindings.
Merge pull request #59 from artillery/webidl-bindings

Rebuild box2d.js and update README
update docs
do not build in emscripten filesystem and browser support, which we don't need
Modification to build within artillery/universe
Merge remote-tracking branch 'upstream/master' into broadphase-filtering

Conflicts:
	box2d.js
Rebuild box2d.js