Add per-process HTTP metrics.
Merge branch 'origin/metrics' into develop
Updated imagetype version (fix #29).
Changed mozjpeg module and install nasm in travis.

Replaced mozjpeg with mozjpeg-bin.
Now uses mozjpeg 2.0 and do the compilation during install instead of first run.
Merge branch 'imgcompression' into develop
Bump version to 0.3.0
Fix cache non-GET request handling.
Merge branch 'fix-cache' into develop
Added url expander plugin.
Removed 'follow-redirect' module.