implement channel removal in amnesiadb

storage/amnesia.js

@@ -19,6 +19,10 @@ module.exports.create = function(conf, cb){
     var db=[],
         index=0;
 
+    if (conf.removeChannels) {
+        console.log("Server is set to remove channels %sms after the last remaining client leaves.", conf.channelRemovalTimeout);
+    }
+
     cb({
         message: function(channelName, content, cb){
             var val = {
@@ -41,5 +45,12 @@ module.exports.create = function(conf, cb){
             });
             if (cb) { cb(); }
         },
+        removeChannel: function (channelName, cb) {
+            var err = false;
+            db = db.filter(function (msg) {
+                return msg.chan !== channelName;
+            });
+            cb(err);
+        },
     });
 };