Add support for XZ compression
Don't require an accept-encoding header for gzip, since SPDY does not require it

Also, gzip a few other mime types
Allow passing mocha args to 'npm test' via $MOCHA_ARGS environment variable
Merge branch 'lzma' into develop
Add debug metrics output in dev environment. gh-10
Add custom StatsD console backend.
Add user-provided metrics clients.
Update metrics production settings.
Cleaner metrics debug output.
Fix config.
Move StatsD backend out of repo.
Merge branch 'metrics' into develop
Fix gif2video
Enable gif2video by default