Assigning permission allows people to possibly deny that permission to hide the command from tab complete list.
Permission is defaulted to true, so command keeps current behavior by default.
* only tabcomplete for commands the sender has permission for
* set permission defaults for spigot
* Make velocity autocomplete on arg length 0 and 1
* fix advancements perm in spigot plugin.yml and add settings perm
(whoops)
* don't show bedrock commands to java players
* modify spigot perm defaults
* censor help menu, abstract tab complete code
* Bedrock players don't get cmd argument suggestions
* update spigot plugin.yml
Despite the Bukkit suffix being correct in terms of the API, the name causes some people to download CraftBukkit instead of Spigot or Paper. All internal references to Bukkit have been renamed to Spigot.
