Create plugin management UI

Using SimplePluginManager as the back-end:

UI should provide:

• Tab for local plugins
  • Local plugins placed in %RECAF%/plugins/
  • Allow toggle on/off plugins (should be persistent)
  • Allow easily loading new plugins
  • Allow easily updating plugin if a new version is found (Can support official plugins, see below)
• Tab for remote plugins
  • We can use the github API (rate limit to only check once per day) to scan for all releases under: https://github.com/Recaf-Plugins
    • Or figure out some other scheme, ideally a freely hosted one that allows easy discovery and is easily updated as a maintainer
  • Show most recent release's changelog (Can refer to the Recaf 2X updater on how to render MD/HTML from release, or make something better)
  • Allow one-click download / immediate install