GitHub's reference list API does not actually restrict the specified type, so don't artificially restrict it.
The API does not actually make a distinction between the "type" and "prefix" at all, but this is maintained for backwards compatibility. The two are simply concatenated.
This plugin is a counterpart to GithubPulls plugin. Instead of fetching pull
requests, it will fetch all references (branches and tags) that start with a
particular prefix.
The plugin is a copy of GithubPulls plugin with appropriate changes to call the
right API and parse the config matching the need.
