Query table for getVertexAttrib

- Add VERTEX_ATTRIB_ARRAY_DIVISOR
- Add VERTEX_ATTRIB_ARRAY_INTEGER
Integer Vertex Attribute return values, getSamplerParameter and getInternalformatParameter

Add return types for Integer Vertex Attribute return values.

Describe how the getVertexAttrib method will return attributes loaded
via vertexAttribI* family.
Removing unused CSS class
Remove TODO from generated IDL
Merge pull request #576 from grorg/remainder-query-tables

Query tables for getVertexAttrib and getSamplerParameter