Merge pull request #632 from mariroz/dev

logging by import added; error by creation table if exists in postgresql...
Merge pull request #633 from mariroz/dev

error with empty content by import fixed. Also youtube and vimeo videos are allowd in content now.
1.6.1 version
added missing image to dmagenta theme
Merge pull request #635 from DmitrySandalov/dev

added missing image to dmagenta theme
Improved french translation
Merge pull request #637 from Bubbendorf/dev

Improvements on french translation
Added IF NOT EXISTS
Merge pull request #642 from jplock/patch-2

Added IF NOT EXISTS
[fix] rss feed content type set to text/xml #636
Merge pull request #643 from wallabag/fix-636

[fix] rss feed content type set to text/xml #636
print view fixed in baggy; print link added; read percent added in default theme; archive and favorite re-factored to be ajax action in article view