Merge pull request #284 from zlamalp/spell

GUI: fixed spelling authentications -> authentication
Merge pull request #285 from zlamalp/help

GUI: added link in footer to online docs
Merge pull request #286 from zlamalp/fixes

GUI: fixed create group dialog
Merge pull request #289 from zlamalp/fixup

GUI: fixed add member to resource dialog
Merge pull request #290 from zlamalp/url

GUI: simplified URL for single tab