Allow colons in identifier values

Fixes #1224885 [<dc:identifier opf:scheme="URI"> and semicolon #2](https://bugs.launchpad.net/calibre/+bug/1224885)
Update Politika
Fix #1225552 [Windows portable executable file description should be "Calibre"](https://bugs.launchpad.net/calibre/+bug/1225552)
Book list should track edit metadata dialog

Fix regression in 1.3 that caused the book list to not track the
ecurrent book when using Next/Previous in the edit metadata dialog.
Fix #1225499 [non translatable "completed" for completed jobs](https://bugs.launchpad.net/calibre/+bug/1225499)
Merge pull request #84 from cbhaley/master

Have metadata.book.set_all_user_metadata actually set the metadata, not ...
When copying books from library A to library B, check that B contains the necessary custom columns. If not, tell the user and allow them to create any non-conflicting columns. Inform them about conflicting columns.