Fix #1335468 [Editor: ValueError: No JSON object could be decoded](https://bugs.launchpad.net/calibre/+bug/1335468)
Fix #1332837 [Additional article words in Italian](https://bugs.launchpad.net/calibre/+bug/1332837)
Fix #1335598 [corrupted tooltip with very long tweak setting](https://bugs.launchpad.net/calibre/+bug/1335598) and pep8