Complete Softmute (Vanilla version)

2.0.1: No functional changes, minute optimization
Decided to upload this since I might've uploaded an incorrect version last time. Either that, or I uploaded a version where I forgot to change the version number in plugin.yml

2.0: Updated to changes in GriefPrevention 13.1
This is why:
https://github.com/ryanhamshire/GriefPrevention/commit/37851aacbf8d507d334652250b24ec20844f58bf

I guess it's not that big of a deal, technically I don't need to worry about figuring out whether to cancel or not, since I'm now always expecting the event to be cancelled. But it'd be even better if I didn't have to listen to commandpreprocess events at all and instead a custom listener, if Big_Scary ever decides to implement one.

1.2: Bug fixes
- Fixed a "compatibility" check (incorrect case for a plugin name)
- Added compatibility for BlockSyntax (and other potential anti-spam plugins)
- Slight refactor of the event "uncanceller" (some cleanup, readability)

1.1.1: Slight Optimizations
Slightly optimized the commandpreprocess event handler to only create and set variables only when necessary.

1.1.0:
- Added softmute functionality to /ignored whispers
- If recipient has /ignored the sender, the sender gets a "softmute" message.
- If sender has ignored recipient, the sender is told that they need to /unignore the player first before sending a whisper.
- Code refactoring
- Potential compatibility with plugins that block /plugin:command syntax. If this does not appear to be the case, let me know what plugin it is!

Will not work as expected with versions of GriefPrevention below 13.1