Merge pull request #125 from HeikoAdams/master

Some more german translations
rebase translations
release 1.7.6
French translation update - a few new strings, few not-so-fuzzy strings fixed
Merge pull request #126 from RaphaelRochet/master

French translation update
add an angrier blurb to sanity_check.php
Update few typos and directly visible strings after the release.
Merge pull request #127 from scarabeusiv/master

Fix typos in czech trans and add few directly visible strings
add NO_CURL; disable native gzdecoding for file_get_contents() experimentally
Merge branch 'master' of github.com:gothfox/Tiny-Tiny-RSS
fix catchup not working on Fresh articles
updater: add /bin and /usr/bin to path before looking for binaries in case of php-fpm empty environment or whatever
installer: remove shorttag
fix default sorting not taking score into account, remove unused SORT_HEADLINES_BY_FEED_DATE remnant
replace catchupCurrentFeed dropdown with a better control
remove session check/destroy stuff, looks problematic
deinitialize session in login_sequence() instead of sessions.php
only destroy unlogged sessions
plugins/mail: remove secretkey stuff
updater: fix is_writable checking