Added the option to set user defined bounding sphere of a Lod, also added the related computeBound function
Test for UserDefined BoundingSpheres
Adds StateSet UpdateCallback

Not sure it was a good idea to use an array instead of linked list.
It's more convienent to use array but has an overhead on all StateSet /
Node. To be consistent we should replace all callback system with array,
if we keep this way to do it.
JsHint + JsFormat pass
Merge pull request #69 from Teybeo/feature/composer_examples

Rewrite the postprocess example to use Composer and new effects
Merge pull request #77 from cedricpinson/add-statesetUpdateCallback

Adds StateSet UpdateCallback
Merge pull request #76 from jtorresfabra/LOD_UserDefinedBound

Added the option to set user defined bounding sphere of a Lod, also adde...
More jshint and misc fixes

Fixes "Uncaught ReferenceError: count is not defined"