Expose the mining area of mining drills

[cpw]

Simple request to fulfill the needs of my mod proposition: https://forums.factorio.com/forum/vie ... 33&t=16179

Expose the properties necessary to compute the available resources within a mining drill's range, so that it can be output on the circuit network (in this case).

In discussion with Rseding91 on IRC, I believe the only thing missing is the mining area of the drill. Which I would assume would be specified as the corners of a rectangle which the drill can see. With that, it should be possible to query the world on a regular basis within that rectangle, retrieve the ore resources and multiply out (possibly including things like module effects).