A few new features and some integration

+ Refactored some commands to reduce code duplication with commands that
set and toggle boolean options
+ Added -s option to /qt cuboid that sets the primary and secondary
coords using the worldedit selection
+ Added -v option to /qt cuboid that sets the current worldedit
selection to the cuboid region of the QT
+ Added -t option to /qt cuboid which uses the targeted block instead of
the block the player is standing on
+ Added /qt cfg command for setting configuration options in-game
+ Added /qt reload command to fully reload the plugin when changing
global options
+ Added /qt delete command for deleting QT's
+ Added enable-fx config option to enable/disable effects
+ Added customisable welcome text to QT's that can be set using /qt
welcome <qtname> <message>
+ Added qt.fromanywhere permission which can be granted to players to
allow QT from anywhere when QT from anywhere is disabled globally
+ Added basic support for showing QT's on Dynmap
+ Added some basic validation to all numeric options, should hopefully
prevent derpiness caused by setting of invalid values
+ Fixed a problem with QT's not working when economy was disabled
+ Fixed an NPE when specifying a world name with -w that doesn't exist