Changelog
* 55431e3 Add support for build secrets (1010)
* 69e2046 Add test for getting media type by extension
* a0c18e5 Define custom media type / extension mappings, falling back to mime
* 1e5ef7d Define media types for .jsonl and .ndjson file extensions
* 92a5b7c Document environment variables.
* b2789cd Record git commit on images (1008)
* 28ac8dd Remove cog.director and cog.server.redis_queue
* 2df5d59 Remove unused fixtures
* 4b1c3e9 Sort and group media types by primary type
* d66af7c Use the configured Python to run pip
* ad653fd Use wrapped mime.TypeByExtension function
* 8d63499 update .all-contributorsrc [skip ci]
* 8feeb07 update README.md [skip ci]