Added epub export function
Fixed a bug into PHPePub with special caracters
Merge pull request #667 from mariroz/dev

fix of putenv warning under safe mode, issue #646
Big changes for epub export. Now possible to do it from a tag, a category and a search. Also, improved ebook rendering.
Changed template organisation
Added save search as tag functionality
Remove unnecessary line
Clean old unused tags when deleting a tag
#568 missing rss.png files
Many improvements to epub produced : better cover, better tags
Added translation capabilities for epub system
Updated the french translation
Added advices to submit a bug

Discussion at #662.
Merge branch 'dev' of https://github.com/wallabag/wallabag into dev
Removed unnecessary function for cleaning tags
Merge pull request #680 from m-r-r/fr-1.6.1

French translation update
Simplifed function which does tag cleanup
Changed theme for better translation method
Merge branch 'dev' of https://github.com/wallabag/wallabag into epub
Fix bugs and improved epub rendering