Even more incomplete changes

- Fixed commandPermissible method calls for commands referring to the
wrong permissions (oops)
- Changed "ignore-command-permissions" option in config.yml to the
slightly more descriptive "ye-olde-command-system"
- Fixed both /mvtpf and /mvtpfstatus both using
multiverse.teleportfilter.status, now /mvtpf uses
multiverse.teleportfilter.info instead
- Started work on /mvtpffilter list
- Miscellaneous comment/documentation changes