re: assembla/#169 Second source field mapping dissapears

* includes/Config.php
  - added resource jquery.json

* includes/Forms/MetadataMappingForm.php
  - added ids to form tables

* resources/js/ext.gwtoolset.js
  - added logic to handle cookies in order to store/restore
   input/select fields added with js

Change-Id: I427e0fab539a85bb958d03dd9003d48982cb897f