Check for GnuTLS >= 2.11 only if we have GnuTLS >= 2.2
fix wrong gnuTLS: yes when no.
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”