Clicking on the preview panel moves the cursor to corresponding location in the editor
Fix bug #1251768 by allowing case changes when editing any text-based custom column directly on the spreadsheet.
Implement position sync from editor to preview panel
Fix editing custom column values in the book list not allowing change of case. Fixes #1251768 [[Glitch] Case change in library list cell](https://bugs.launchpad.net/calibre/+bug/1251768)

Merge branch 'master' of https://github.com/cbhaley/calibre