Blank Programmables?

[GopherAtl]

all the ProgrammableBlock/TileEntity types - PRB, BioLock, and Keypad - should implement an isBlank() method, and should drop a generic instead of a unique ID'd instance when broken if isBlank() is true, so they will stack.

Low priority, and might end up bypassing entirely if the major overhaul planned for the mc 1.8 update ends up using memory cards