(DRAFT) Livelit PR

This merge brings a implementation of Livelits, with some constant examples.

Examples:

1. Emotion (smile flashing bug?)
2. Timestamp (Can't keep up)
3. Slider
4. JS (Can't save result?)

Issues:

1. CRITICAL: Crash on reload: https://github.com/hazelgrove/hazel/issues/1440
2. Cannot define Livelits during runtime, Livelits don't have access to context -- this needs to be revealed to projectors
3. Cannot implement splices, similarly, requires context
4. Livelit invocation must be directly surrounded by a parenthesis in order to be grouped in InfoExp; example: (^emotion(100)) -- this is a limitation of projectors
5. Cannot define Livelit model, projector requires model type to be constant