Check for duplicates in the spine
Fix #1269592 [Edit Book: New unreleased Manifest missing files test is buggy](https://bugs.launchpad.net/calibre/+bug/1269592)
...
...
Add tests for invalid pointer to toc in <spine>
Make setting an incorrect compression quality value non-fatal by forcing incorrect values to the default.
...
Book matching during device connection:
1) add some debugging output
2) add some user feedback that it is happening by changing the status bar and setting a wait cursor.
3) make the book matching during device connection pseudo-multithread by processing GUI events during matching. In particular, this prevents the OS from deciding that calibre has stopped responding.
Only accept non-user and non-network events while processing books.
Prevent setting an incorrect value for compression quality in the wireless driver causing an error

Show a busy cursor while calibre is working on matching books on the
device to books int he library, which can take a while if the user has a
lot of books on the device.

Merge branch 'master' of https://github.com/cbhaley/calibre
Initial import of Patience Diff C implementation from bzr
Get the patience diff module compiling and loading
Add checks for meta cover tag and OPF package identifier
recipe update
Update various Polish news sources

Merge branch 'master' of https://github.com/fenuks/calibre
Fix user manual documentation for calibredb set_metadata incomplete
...
version 1.20
...
Trim changelog