Include the URL of the binary cache in .nixpkg files
Provide the nix-cache-info file required by the binary cache substituter
Add a binary-cache-url file to channels to advertise the binary cache URL
Set the Content-Type properly
Do not send emails when build is cancelled/aborted. Also, ignore aborted/cancelled builds in comparing to previous build.
Add create-user action that was mostly present already.
Show build status for up to 100 jobs in stead of 50.
Fallback for git fetch, which allows specific gits revisions to be used as build inputs.
hydra-eval-jobs: Don't go into an infinite recursion

The function getDerivation() can return false if its argument is a
derivation.  This happens if evaluating the name or system attribute
triggers an assertion.  In that case, we shouldn't recurse into the
attributes of the derivation.
Don't ignore assertion failures in getDerivation()
Add dollar to pathCompRE, which allows files with dollars in them to be served by Hydra, e.g. sphinx generated docs often has these types of files.
Add support for Guile & Guix.
Capture the path to `guile', when available.
release.nix: Add dependency on Guile.
Turn off overly verbose log messages by default

The "Request took ...s" messages are rather spammy, so turn them off
by default.  You can set CATALYST_DEBUG=1 if you need them.
Log time required by a request
Give Hydra binary caches a low priority

We only want to hit a Hydra binary cache if static caches don't
provide a binary.