Check for a location in a certain region.

With this new update in LocationUtils.java, you can use isIn( Location
check, Location point1, Location point2 ) to check if the location
'check' is in the region of 'point1' and 'point2'
useArguments for ECommand

Now you can use ECommand.addSubCommand( String, ECommand ) to add
subCommands after creation. You can even use ECommand.addSubCommand( ...
).addSubCommand( ... ) as it is a builder.