Ignore corrupted conversion config files instead of failling to convert

See #1306854 (Error when trying to convert)
Searching: Fix searching by date not using the system locale to interpret dd/mm vs mm/dd dates
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Update Creative Blog
Fix various warnings from running updated pyflakes on the entire codebase
Workaround for broken linux installs with encoding set to ANSI_X3.4-1968

Got a second bug report from a user running such a system today. So
workaround it.
Amazon metadata download: Fix Editorial Reviews not downloading into the comments section
Make the code that ensures that python internal encodings are not ASCII more robust
Fix #1307397 [Support Tolino Vision (Windows)](https://bugs.launchpad.net/calibre/+bug/1307397)
Fix column coloring to allow #xxxxxx in the GUI processing.
Merge branch 'master' of https://github.com/cbhaley/calibre
Metadata download dialog: Simply the description of the book being searched for and make its font size normal
Fix incorrect syncing behavior when book matching is run for a second time while connected. This happens when the user changes the library or selects "Update cached metadata on device".
Merge branch 'master' of https://github.com/cbhaley/calibre
use gutenweb in attac recipe
use gutenweb in smashing recipe
use gutenweb in list a part recipe
add historias del mundo spanish recipe
add histories del mon catalan recipe
add la vanguardia corresponsales spanish recipe