\#overview vs temples and altars

Reported by entrez:  it was possible for #overview to show a line of
just "." if a temple was known and its altar was unknown and no other
features such as thrones or fountains were known on the level.

It now lists "M temples and N altars" when both are present and the
case that yielded "." becomes "a temple".  That's an improvement but
there might be edge cases it gets wrong.  A listing of "a temple and
an altar" is ambiguous because there isn't any way to tell whether the
altar it mentions is inside the temple.  That seems acceptable to me.

I think it should include more alignment information about temples and
altars, instead of just adding "to <your god>" when all known altars
are of hero's alignment, but this doesn't attempt to address that.

doc/fixes3-7-0.txt

@@ -1258,6 +1258,9 @@ barbed devils have an attack that sticks you to them
 balrogs prefer bullwhip if hero is wielding a weapon
 ice devils have an additional attack, a slowing touch
 buff scroll of confuse monster and blessed potion of monster detection
+if a temple was entered while blind, #overview could show a line of just "."
+	when describing altars if no other interesting features on that level
+	were known
 
 
 Fixes to 3.7.0-x General Problems Exposed Via git Repository