Add Redstonetimer, detailed Description in Commandtimer.java

Timer Command. Very useful for Commandblock-things. It changes after <time> the block at the given Location into a redstone block (Mode: ON); Mode OFF would be Air, and TOGGLE places one if there is none and sets air if there is one ;) | Default is ON | Usage: /timer <x> <y> <z> <time> [mode] | Modes: ON, OFF, TOGGLE