"act" command as automatic variant of "use"

[kostmo]

Building upon #1007...

Whereas the proposed type signature of use is:

use :: entity -> direction -> cmd unit

I propose an additional command act that automatically uses the "best" device to perform an action, similar to the current semantics of drill:

act :: direction -> cmd unit

This would preserve the convenience and interesting gameplay mechanics of drill while shedding the connotations of the drill name.

Implementing this could be as simple as renaming drill to act. Though drill may be re-introduced as a specialization of use.

[byorgey]

See #1286 .