RLG-Web: make login sessions time out.

After enough inactivity, log the user out automatically.

rlgterm.js

@@ -164,6 +164,9 @@ function processMsg(msg) {
   else if (msgDict.t == "E") {
     if (msgDict.c == 1 || msgDict.c == 6 || msgDict.c == 7) {
       gameover();
+      if (msgDict.c == 1) {
+        logout();
+      }
     }
     debug(1, "Server error: " + msgDict.s);
   }
@@ -496,6 +499,9 @@ function startgame(game) {
     }
     else if (reply.t == 'E') {
       debug(1, "Could not start game: " + reply.s);
+      if (reply.c == 1) {
+        logout();
+      }
     }
   };
   req.open('POST', '/play', true);
@@ -551,6 +557,12 @@ function gameover() {
   return;
 }
 
+function logout() {
+  lcred = null;
+  lname = null;
+  setmode("login");
+}
+
 function stop() {
   if (!termemu.sessid)
     return;