* feat(git_branch): add remote branch name if different than local branch
* feat(git_branch): Implement a more customizable remote branch
* feat(git_branch): Use more explicit API function name
* feat(git_branch): Remove forgotten draft documentation
* feat(git_branch): Set less verbose defaults
* feat(git_branch): Handle case to always display remote
* feat(git_branch): Fix error in rebase operation
* feat(git_branch): add 'only_attached' config bool
This adds a new boolean, `only_attached`, to the configuration for
the `git_branch` module. This mirrors the `only_detached` config
value for the `git_commit` module: setting the value to true causes
the module to suppress its output when the user is not on a branch.
This allows users to have either a branch name or a commit hash in
their prompt, as opposed to having either a branch name or the
overly-wordy "HEAD (sha1)".
* Fix formatting
