Test compilation rules related to compute shader layout qualifiers.
Test that compute shader work group sizes are properly bounds checked.
Test ARB_compute_shader built-in constant gl_WorkGroupSize.
Test ARB_compute_shader built-in constant gl_MaxComputeWorkGroupCount.
Test ARB_compute_shader built-in constant gl_MaxComputeWorkGroupSize.
Test that compute shaders may not have user-defined ins/outs.
shader_runner: Add support for compute shaders.

Currently there is no way for shader_runner to accept output from
compute shaders; however this should still be useful for linker tests.
Linker tests for compute shaders: local work sizes.

These tests verify the linker rules for local work sizes (they must be
specified in at least one shader, and they must not conflict).
Test API errors for compute shaders related to COMPUTE_WORK_GROUP_SIZE query.

This test can be expanded in the future to check for other compute
shader API errors.
Revert "framework: Add support for a test timeout"

This reverts commit ab2eb660925e3680e868c5f469a4ef32e6dd9a59.

Conflicts:
	framework/status.py
WIP: loop analysis tests