D15231: Move to use QUrlQuery in favor of deprecated queryItemValue() from QUrl

[Damien Caliste]

dcaliste added a reviewer: Calligra: 3.0.

REPOSITORY
  R8 Calligra

REVISION DETAIL
  https://phabricator.kde.org/D15231

To: dcaliste, leinir, #calligra:_3.0
Cc: Calligra-Devel-list, cochise, vandenoever