Ensure glDeleteBuffers silently processes non-existent names, per spec.
Add sys/sendfile.h
Use single quotes instead of double quotes with cDefine.

This makes these 2 usages match all of the others.
Include signal.h when using signals.
Merge pull request #1461 from waywardmonkeys/cdefine-single-quotes

cDefine should use single quotes
Merge pull request #1462 from waywardmonkeys/include-signal-h

Include signal h
mention DISABLE_GL_EMULATION option when initializing gl emulation
Merge pull request #1460 from yukoba/sys-sendfile-h

Add sys/sendfile.h
Modify glDeleteBuffers changes per azakai's comments.
strip color correction from pngs, so that the browser reftests are consistent across machines
add more slack to test_sdl_rotozoom
always use canonical temp dir in benchmarks, to let multiple tests reuse the same built libraries
infrastructure to track the costs of outlining, and to possibly change outlining thresholds as we go
remove nativizer test output
fix test_fgetc_ungetc
increase logging output, fixes s_0_0.test_safe_heap
handle overflows when relocating heap offsets
handle IPv6 addresses in inet_ntop and inet_pton
Coding conventions fix.
Merge pull request #1459 from j4m3z0r/gl_delete_buffers_nocrash

Ensure glDeleteBuffers silently processes non-existent names, per spec.