Add /ignore command

[mdcfe]

Add a /ignore command which lets players mark other players as ignored. Running /ignore bob will toggle whether "bob" is ignored or not, but this can be overridden by adding true/false at the end. A list of ignored players is available through the API and by running /ignore with no arguments.

[Crypnotic]

Make sure you're adding the message to the default locale

[mdcfe]

@Crypnotic I've updated the en_us locale file.

[LarsArtmann]

@md678685 Where you call "ignore_ambiguous_player"? I can not transate it, good.

[mdcfe]

@LartyHD ignore_ambiguous_player is shown if there is more than one person whose name matches what the user typed after /ignore. For example, if you run /ignore bob when there are players called "bob1" and "bob2", it will send ignore_ambiguous_player instead of picking one of those players.

@Crypnotic Should the matchPlayer argument parsing be moved to CommandWrapper and used throughout all the commands?