Open file dialog size is not responsive

[pcav]

if I open QField on portrait orientation, then I rotate the screen, the visualization gets unusable. See attached. Nexus 6p, QField 0.8.6

[m-kuhn]

For reference

The file dialog is not really suitable for QML visualization and has
several usability problems. However, it's the best thing we could find
that's available out of the box from Qt.

A fix will probably require rewriting our own file dialog and therefore
unfortunately not trivial.

http://lists.qfield.org/pipermail/users-qfield.org/2016-October/000005.html

[mbernasocchi]

@m-kuhn https://stackoverflow.com/questions/15079406/qt-necessitas-reasonable-qfiledialog-replacement-skin

[mbernasocchi]

and http://doc.qt.io/qt-5/qml-qtquick-dialogs-filedialog.html

[signedav]

In case #232 is solved, this will be probably be not anymore an issue.