Re-enable the short inactivity timeout for non-terminal connections (bots)

As of Oct-25-2018, the NO_EXASCII flag was set in the autoterm variable
when there was no ANSI terminal auto-detected. This defeated the short
inactivity timeout feature of login.js because it was checking specifically
for a zero-value autoterm.

So change this logic to check for no ANSI, PETSCII, or UTF-8 (the 3 indicators
of a valid terminal) - though I suppose PETSCII is questionable (it's not
actually auto-detected, just a non-standard port usually).

exec/login.js

@@ -24,7 +24,7 @@ var guest = options.guest && system.matchuser("guest");
 
 if(!bbs.online)
 	exit();
-if(!console.autoterm) {
+if(!(console.autoterm&(USER_ANSI | USER_PETSCII | USER_UTF8))) {
 	console.inactivity_hangup = options.inactive_hangup;
 	log(LOG_NOTICE, "terminal not detected, reducing inactivity hang-up timeout to " + console.inactivity_hangup + " seconds");
 }