Simplified timers again, now makes use of BukkitRunnables.
There is still some room for improvements, but this system is way
simpler and stable than the old one.
Moved a lot of code into CommandUtils, added player-only commands
While this removes some flexibility when it comes to error messages,
it simplifies updating and adding of additional features like dynamic
warp-suggestion because they are handled all in one place.
This also allows us to switch to a new, annotation-based command handler
without needing to rewrite larger parts.
Fixed /warp remove, some minor clean up
Added warp suggestions based on visits-count