Added a reset. The format is the same as 'dirt to tnt' except you put '[reset]' on the first line and it replaces all of the TNT in that area with dirt.
v.0.5
Fixed a bug where you had to fill in all 4 lines or it wouldn't work.
v.0.4
Added the option of choosing height and depth
made sure it works with the newest available bukkit Minecraft1.8 build (1124)
also fixed a few small mistakes.
v:0.3:
Added being able to choose your radius on the second line of the sign.
