Improve quaternion API.

Fix norm() (which is norm squared right now).
Add Matrix4x4 initialization from Quaternion instead of Vector4.
Add normalize().
Add Quaternion initialization from axis rotation.
Make default values unit.
Add methods to create a quaternion from a rotation between two vectors.
Proposed a quick fix to use the specular map not only as a modulation function for Phong, but as masking for environment mapping.
Nicer handing of Viewport dispose and invalidation of primitive geometry instances on context dispose.
Add a name attribute
Colored shadow added

Colored shadow added
Merge branch 'dev' of https://github.com/aerys/minko into dev
Added ParserOptions.materialFunction.
Fixed the ParserOptions.defaultDependencyFunction.
Fixed the ParserOptions.defaultDependencyFunction.
Add geometry dataprovider that reference vertexcomponents
Optimization on shadows that fix problems with spotlights
add support for BitmapData as a source for DynamicTextureController
fix DiffuseShaderPart.getDiffuseColor() to use vertexUV if the provided uv argument is null
unmark CameraController as final
minor fixes
setup the Viewport using the baseline profile by default (instead of the not yet available extended profile)
fix Phong reflection model inconsistencies between single pass and multi pass modes
fix multipass lighting passes order
Remove comments
Fix sprite shader