Edit Book: Fix a typo that would cause an error when a global operation like find/replace or polishing fails. Fixes #1275366 ['Edit Book' corrupts epub when find & replace fails](https://bugs.launchpad.net/calibre/+bug/1275366)
Merge branch 'master' of https://github.com/t3d/calibre
Stricter test for author match from edelweiss.com
Fix #1275394 [tweak for naming in Editor checkpoints](https://bugs.launchpad.net/calibre/+bug/1275394)
Edit book: Do not create savepoints when no changes are performed by automated tools such as smarten punctuation, remove unused css etc.
When rewinding checkpoints preserve the message
Make it clear when reverting that the checkpoint is no longer necessarily what it originally was
Remove trailing checkpoints when user does some editing on the current chackpoint
Update wired.it
Disinformatico by isspro
Revert the truncation of the checkpoint list on editor modification since the modified signal is not reliable (it can be triggered bythings that are not changes as well as not triggered for changes if the editor is already in the modified state).
Update Cosmopolitan UK
Edit book: Check book, detect case mismatches between links and the filenames of the files they point to and offer to auto-correct the links

Works on both case-insensitive and case-sensitive file systems
Markdown input: Fix handling of very large files. Fixes #1212330 [Markdown converter produces garbled output on large files](https://bugs.launchpad.net/calibre/+bug/1212330)
Update Kathimerini
Remove unused image
...
Edit Book: Highlight the closest surrounding tag when editing HTML/XML
...
Update source code links