Allow Uint16Arrays uploads for texture_half_float
Specify reading from missing attachments

readPixels/copyTexImage2D/copyTexSubImage2D should generate INVALID_OP when reading from a missing attachment.
Changed oes-texture-float-and-half-float-linear tests to allow failure during glGenerateMipmap. This addresses https://github.com/KhronosGroup/WebGL/issues/408 .
Verify if component values are set correct

GLSL constructors : Added code to verify if component values are set
correct by constructor expression.
moved EXT_sRGB from draft to community approved
moved EXT_frag_depth to community approved
Add coverage of uniform structures with non-vec4 elements.

Triggers a uniform packing bug in ANGLE's D3D11 backend.
Merge pull request #558 from vonture/master

Add coverage of uniform structures with non-vec4 elements.
Added link to IP disclosures. Cleaned up name references.
Merge pull request #559 from kenrussell/ip-disclosures

Added link to IP disclosures. Cleaned up name references.
Updated cross-origin test in more/functions/texSubImage2DHTML to use newer methodology
Also applying fixes to texImage2DHTML
Merge pull request #560 from toji/cross-origin-2

Updated cross-origin test in more/functions/texSubImage2DHTML
Use union types instead of overloading for buffer[Sub]Data and tex[Sub]Image2D.

This fixes https://www.khronos.org/bugzilla/show_bug.cgi?id=1172 .
Use a relative rather than an absolute link for the specs/ redirect.

This simplifies local testing of spec changes.
Merge pull request #561 from kenrussell/relative-redirect

Use a relative rather than an absolute link for the specs/ redirect.
Added text to all new interfaces except WebGLSync, which I'm not terribly familiar with
Made the latest spec landing page slightly more useful
Added desriptions of VertexArray functions
Added conformance test for EXT_blend_minmax