Add only_has_contributors_in predicate (#114)
The new only_has_contributors_in predicate is similar to has_contributor_in, but applies to all contributors on a pull request, including the pull request author. This is useful to enable special approval conditions when a mix of trusted users and/or automated bots have contributed to a pull request.
Add ability to read some configuration values from the environment (#113)
All GitHub options and certain sensitive Policy Bot options can be defined or overridden by environment variables. The exact properties and environment variable names are described in the sample configuration file.
Fix caching when a pull request contains no changed files (#105)
Previously, if a pull request had no files, the file cache for a request was never initialized. When a policy has many file-based rules, this can lead to a huge number of unnecessary API requests and delay evaluation.