Reset all undo actions when calling -setAttributedStringValue:
Force main thread
Reset before reloads
New plugin API

Goals of update THOPluginProtocol implementation:

1. Update all method names to have the name fit their actual purposes.
2. Add additional, critical features that were previously difficult to
handle without going through a lot of work.
3. Keep the old API calls but also deprecate them to allow backwards
compatibility for now.

The changes were more aesthetics (e.g. name changes) but still paving a
way for something better.
Fix method name
Migrate to new API
Migrate to new API
Post deprecation warnings
Repair name
Rewrite API before its used
Add one more key
Fix selector name
Make sure keys exists even when they don't
Small tweak
Introduce a plugin method for accessing renderer
Add .innerMessage span to make accessing inner message easier.
Pass additional information
Small typo
Another typo
Assign correct length