implement RFC 3196, 'When changing quicksearch Search Type, set focus to search input box'

and simplify a bit
fix bug 3170, 'QuickSearch fights with View/Hide read threads menu option'
Probable fix for Debian bug 730050 “vcalendar plugin crash”
Reintegrate RSSyl's don't-mark-as-unread translations from 3.9.3. Fix the fuzzy ones where "Never mark as unread" was translated the same as "Always mark as unread" in at least 8 languages, by removing them.
fix wrong fuzzies
Fix use after free
Don't close FILE we don't own
Fix another use-after-free
Another wrong free
Fix off-by-one
Fix missing mutex accessing _displayQueue_
Fix g_stat return value unchecked
Fix Coverity issues
Fix missing NULL checks
Coverity fixes
Finish previous fix
Coverity fixes
Coverity fixes
Fix wrong binary logic
Wrong fix