A simple plugin that introduces an alternative to the classic idea of picking up a mob spawner as an item using silk touch. With Shiftable Spawners you can shift a mob spawner a single block from it's current location using a golden pickaxe enchanted with silk touch and a small amount of experience points. Simultaneously adding a use for at least one of the gold tools and a large cost to moving the spawner any large distance.
When a mob spawner is broken with a silk touch golden pickaxe, it will shift to one of the blocks directly next to it as long as the block is air and has a solid block below it. This means that in order to move a spawner you need to block every location where the spawner could go within a 1 block square radius around the spawner, think a 3x3 cube centered on the spawner, except for the one spot where you want it to go. The spawner will never shift on top of itself. It will only shift to air blocks. It needs a solid block below it, IE one you can walk on. If it can't find a block that meets these requirements the spawner will not break, but the xp cost will still be taken.
The XP cost is configurable, but by default it will use the amount of xp that the spawner would have given if it had broken normally, a value between 15 and 43 xp points.
If the golden pickaxe has mending, you will consume 1 experience point to mend the golden tool instead of consuming durability. This is affected by unbreaking and is also configurable.
