Version 1.1.6

Fixed support for latest versions of Qt by the :QHelp command (thanks to Dmitry Frank).
Fixed regular expression for filtering help tags (thanks to Dmitry Frank).
Fixed issue with 'shellslash' option on Windows (thanks to Dmitry Frank).
Don't escape g:qthelp_browser on invocation (thanks to Dmitry Frank).
Added g:qthelp_tags option (thanks to Dmitry Frank).