Fixed: Wrong background color stored for elements selected through clickhide

Review: http://codereview.adblockplus.org/5661044793933824/
Updated dependencies
Updated translations from Crowdin
Removed images from metadata.common that are no longer being used
Fixed unit tests

Review: http://codereview.adblockplus.org/6444238522810368/
Releasing Adblock Plus 1.7
Added tag 1.7 for changeset aa7f458dec29