fixed how channels and users are cached

src/channel.js

@@ -5,6 +5,7 @@ class Channel {
         this.name = data.name;
         this.type = data.type;
         this.id = data.id;
+        this.messages = [];
         //this.isPrivate = isPrivate; //not sure about the implementation of this...
     }
 
@@ -15,6 +16,22 @@ class Channel {
     equals(object) {
         return object.id === this.id;
     }
+    
+    addMessage(data){
+		if(!this.getMessage("id", data.id)){
+			this.messages.push(data);
+		}
+		return this.getMessage("id", data.id);
+	}
+    
+    getMessage(key, value){
+		for(var message of this.messages){
+			if(message[key] === value){
+				return message;
+			}
+		}
+		return null;
+	}
 
 }