Fixed soumak77#110 - Remove leading slashes in updates before using key

Author: rhodgkins

src/firebase.js

@@ -194,7 +194,7 @@ MockFirebase.prototype.update = function (changes, callback) {
         // operate as a multi-set
         _.keys(changes).forEach(function (key) {
           var val = changes[key];
-          _.set(data, key.replace(/\//g, '.'), _.isObject(val) ? utils.updateToRtdbObject(val) : val);
+          _.set(data, key.replace(/^\//, '').replace(/\//g, '.'), _.isObject(val) ? utils.updateToRtdbObject(val) : val);
         });
         data = utils.removeEmptyRtdbProperties(data);
         self._dataChanged(data);