Fix #1333932 [Edit Book: Double-click on a file category raises a error](https://bugs.launchpad.net/calibre/+bug/1333932)
Fix #1333944 [Edit Book: Strange error when deleting style](https://bugs.launchpad.net/calibre/+bug/1333944)
...
...
...
added re_group function
list_re_group template function. Clean up re_group function. Add documentation
Template language: Add a new function (group_re) to use grouping regular expressions with groups, where you can replace the matched groups with result of another template

Merge branch 'master' of https://github.com/cbhaley/calibre
...
UI for new Add Cover tool