NH4: Require "q," to quaff from sinks/fountains

Compared to NetHack4, this factors out the repeated terrain conditional,
and uses UnNetHack's warning function when the zeroobj case is reached
without terrain set.

Move quaffing from fountains/sinks from qy to q,
Alex Smith <ais523@bham.ac.uk>
a1131654208de6ffd04dd8b664d7f5cfab888d74
Fix "Unknown direction" msg at targeting prompt

That message previous appeared when pressing an unhandled key at the map
position targeting prompt, which was nonsense.  This fixes it to read
"Unknown targeting key."

This bug also exists in upstream NitroHack and NetHack4.
Let '@' move targeting position cursor to player

Suggested in #nethack by b_jonas about 30 minutes ago, and was also just
added to NAO by paxed.