code: function() {
        var ids = [];
        // search localstorage for saved documents
        for ( var i = 0, max = localStorage.length; i < max; i++) {
          var key = localStorage.key(i);
          // value is a document if key confirms to prefix
          if (key.indexOf(prefix) == 0) {
            ids.push(key.substring(prefix.length));
          }
        }
        return ids;
      }
docs: Gets all document ids found in the local storage object.
  
  @returns {Array} an Array of document ids