Change how command help is called

[UndeadScythes]

Currently command help is displayed if the player uses /command help. Change this so that command specific help is displayed as a last resort from within the command executor or as a sub command with page numbers (if applicable) so that commands that accept strings as arguments are not incorrectly redirected.

Include sendHelp(int page) and sendHelp() in wrapper and call from command executors.

Addresses #4.
Will resolve #3.