Port to the new QUrl API

Port to the new QUrl API

The use of any broken-down components of the query now needs
QUrlQuery.

The QUrl constructor and toString() are now rehabilitated and the
preferred forms. Use toEncoded() and fromEncoded() now only when we
need to store data in a QByteArray or the data comes from a QByteArray
anyway. Change to toString() or the constructor if the data was in a
QString.

Change-Id: I9d761a628bef9c70185a48e927a61779a1642342
Reviewed-by: Lars Knoll <lars.knoll@nokia.com>