Creates new issues when conditions are met after previous issues are closed

[Stargator]

If none of the issues Arborist created are opened, then Arborist should create a new issue for any valid condition.

Those conditions are:

• Arborist creates an issue for a branch that doesn't meet naming convention
• Arborist creates an issue for Pull Request that is closed, but the branch hasn't been deleted after a period of time defined in the config.
• Arborist creates an issue for Pull Request that is merged, but the branch hasn't been deleted after a period of time defined in the config.