Cleanup default methods
Fix handling of not-inheritable permissions. Fixes #1386
Fix handling of default groups for null world
Bump Bukkit dependency to 1.7.8
Add command to bulk-convert users to UUID now that Bukkit's OfflinePlayer objects are more likely to return a valid uuid
Modify autoupdater to only update between bugfix releases
Release version 1.21
Prepare for development on 1.21.2
Fix issue with certain option configurations breaking prefixes and suffixes