Title Editor, Exercise Keying with UUID, Mutant Editing, and New Persistent State Type

[russell-rozenbaum]

Goal
Implement the ability to make changes to the exercise title while in instructor mode. These changes should persist through page refreshes, switching between exercise slides, and in exercise exports.

Convert exercise mode's local storage keying system from (string, int) pairs to Uuidm types

Implementation Strategy

1. Edit the title cell through which the title is currently rendered, giving it three different states to be in – student mode, instructor mode/editing, instructor mode/not editing
2. Add update actions "UpdateTitle" which contains the string value to update the title with
3. Add a UI pencil icon to give user ability to edit title string
4. Add UI check and x icons for user to confirm or cancel title changes, respectively

Added Features

1. Title box has a pencil next to it which user can click when in instructor mode to begin editing title
2. User can then either click confirm or cancel icons to save or delete changes to title, respectively
3. Saved title gets saved to the exercise state, leaving spec unmodified
4. New titles are saved and loaded from local storage on page refresh and exported in exercise module exports
5. Exercise's storage keying system now uses UUIDs rather than (string, int) pairs. *Note: this change removes the previous version field, represented by the int in the pair of the old keying system
6. Made a mutant editing suite where instructors can add, delete, and edit mutants
7. persistent_state type in exercise mode has been made into a record. Along with the zipper position and editors it stores the title and list of mutants. This allows for mutants to be persisted and unpersisted upon saving and loading to and form local storage.

Potential Pitfalls

• Exercise modules must have a hardcoded UUID in their spec file to save and load properly. A potential solution can be to initialize a UUID and update the spec when first loading. This would require mutating the spec file however.
• Future implementations requiring saving and loading mutable features to and from storage will need to be added in the record and persisted/unpersisted properly in their respective functions

[cyrus-]

@russell-rozenbaum did you intend to close this issue?

[russell-rozenbaum]

I've added more changes beyond just the title editor to this branch, to be exact I added some implementations to adding and deleting buggy implementations, so I wasn't sure whether to move those commits to a different branch or finish them out fully before opening this pull request

[russell-rozenbaum]

Commit [968fe1c] is the one I'd like to merge. The last 2 commits add the ability to add/delete buggy implementations, which I'll start on another branch. The problem with the current version is a bug that occurs when adding a wrong implementation (which is itself an editor) and then I believe the program does not know where to put the cursor on page reload since the editors are reset (the one previously added, now deleted on page reload), and results in an infinite loading screen. Besides this, I still want to add the ability to edit the hints associated with buggy implementations, which right now defaults to "no hint available".

[cyrus-]

@russell-rozenbaum there are some merge conflicts and a build failure here