more tests, added ability to remove clients from a channel

dist/server/channels/channelBase.js

@@ -26,6 +26,17 @@ class ChannelBase {
         }
         return null;
     }
+    removeClient(id) {
+        var index = 0;
+        for (let client of this.clients) {
+            if (client.id == id) {
+                this.clients.splice(index, 1);
+                return true;
+            }
+            index++;
+        }
+        return false;
+    }
     broadcastMessage(from, message) {
         for (let client of this.clients) {
             if (client != from) {