User (= coder) commands. For example: people, ls, ed, tail, more, man etc.

When making commands, note the following:

-	command giver is TP (this_player()), NOT this_object()!!!
-	can't use living/player variables directly!
-	simply environment() doesn't point to our environment, it has
	to be environment(TP)
-	make sure that every command has that
	if (!CHECK) return 0;
-	MUST NEVER use input_to with these!
-	must be very careful with call_out
