This update just contains a few small fixes since the last version.

• Fix caches not being invalidated when group data changed (woops)
  
• Fixed an issue where Bukkit attachment permissions would never be removed
• A few small performance optimizations
• Add "from_group" and "not_from_group" meta stack elements
• Fix world rewrite operations not being applied in Vault lookups
• Fixed saving node attributes on non-YAML file storage types
• Provide an even more detailed warning message when other uuids are present for a username
  
• Fix regex permissions not really working properly
• Add workaround for plugins adding/removing/modifying permission attachments via reflection (should hopefully fix the incompatibility issues with MassiveCore)

p.s. I released a new plugin a couple of days ago, you should totally go have a look, if you want, maybe, err. bye!