i965: Add gl_InvocationID in tessellation control shader.

Chris: - got rid of spurious addc
       - fixed mask & shift; we have two instances per shader dispatch
i965: Add gl_TessCoord in tessellation evaluation shader.
i965: Track tessellation shader sampler usage.
i965: Track new tessellation shader state.
i965: hs: add custom emit vertex code

XXX: combine with "i965: tessellation level output" and/or "i965: hs: tightly pack per-patch outputs."?
i965: tessellation level output
i965: hs: tightly pack per-patch outputs.
i965: fix crash if no TES
i965: fix INTEL_DEBUG=optimizer for hs/ds
i965/hs: HACK: Pull out num_vertices
i965: fixup ds visitor gen
i965: fixup hs visitor gen
i965: hack hs state emit to require hs & ds to activate
i965: route IsPatch from prog to vue map
i965: fix tess vue map computation
i965: Only output hs patch attribs
i965: dont eat all the memory
i965: ds: layout
i965: disable assert
i965: fixup