CC-5405 When editing a single show instance from a repeating series, should not create a new cc_show

Changed how we store an edited repeating instance in the database.

We no longer create a new cc_show entry, but instead keep the same cc_show id and create a new rule in cc_show_days with a repeat type of -1

There were a number of changes to the current code base we had to change to make this work:

- Determine when the user is modifying the entire repeat show, or just a single instance
- Work with different object sets depending on the above answer
- Change the resize show functionality
- Change the context menu options for edited instances