Fix: Use empty array if there are no categories in the hash
Fixed Command.is_command? check, as prefixes get checked by Regexp
The LimitTagCommand classes have no arguments, they are the arguments to themselves
Ensure we iterate over something non-nil in here
The TagCommand shouldnt work with +<tag>
We must pass the callstring to the Command instance for the TagCommand classes
Added some debugging output
We must check against the callstring here, not the arguments (as we have no args)
If we have a prefix as identifier, we use this one instead as key string
Added help strings
This stuff can be protected in here
We must replace the appropriate identifier in here
Merge pull request #67 from matthiasbeyer/implement-limit_by_metadata

Implement the LimitMetadataCommand classes