Unapproved comments delete

A simple module to delete unapproved comments after a certain amount of day. The number of days is configurable per content type. The deletion process can be done during the cron or via a manual batch. A drush integration is also provided.

Next steps:
- Allow contributor to override the number of day on a node basis.
- Update the setting table to display specific node settings.
- Improve the setting table to display the number of comment per content type which will be deleted during next cron(s).
- Add a direct link on the setting table to launch a batch operation on a specific content type.