This decouples Command from CommandMap, and moves the burden of tracking registered
aliases to CommandMap. This allows lots of simplification, and also solves a few
weird usage message issues.
- Active (registered) aliases are now tracked via CommandMapEntry
- Commands overriding other commands' aliases now update the original command's registered alias list properly
- Command alias lists now include prefixed aliases
- Prefixed aliases are now included in command data provided to the client
- Server-side /pocketmine:help is now visible on the client
- Permission testing can now provide context that's more relevant to the command invocation - e.g. if a user doesn't have /time set permission, it'll now show a more specific message where previously it would just show that the permission for /time was denied
- User-specified label is now used for permission messages instead of command name - this is more consistent with user expectations
- /help can now see prefixed aliases
- Removed magic alias registration behaviour for VanillaCommand that I don't think anyone expected
- Aliases are now provided to CommandMap via register() parameters, instead of being retrieved from the provided Command
- Command->get/setAliases(), get/setLabel() and getName() are removed
- Command->getName() pushed down to PluginCommand, as it's only useful for CommandExecutors as a command ID and shouldn't be used anywhere else
this is intended to replace PluginCommand and CommandExecutor, both of which are overengineered and unfit for purpose.
Allowing a closure allows much greater flexibility.
We can't use this within the core yet, as plugins will expect PluginBase->getCommand() to return PluginCommand (with its associated setExecutor() and similar APIs).
However, I think this is useful enough to add by itself.
