code: function readData (database, key, defaultValue) {
    var deferred = q.defer();
  
    // We need to verify that the database is open and ready
    openDatabase(database).then(function () {
      // Return data, or, defaultValue if no data is found
      deferred.resolve(databases[database][key] || defaultValue);
    }, function (err) {
      deferred.reject(err);
    });
  
    return deferred.promise;
  }
docs: Takes a database name, and key. It returns the data stored in the database
  under the specified key (or defaultValue if it doesn't exist)
  
  @param  {string}   database     Database name you'd like to open
  @param  {string}   key          Key to retrieve data from
  @param  {anything} defaultValue The default return if no data is found for key
  @return {promise} Data is returned as first argument to success callback