fixes#150: Now basically everything is inside a loader; ChatInformationPage is added to ChatPage with pageStack.pushAttached
fixes#166: Replaces the clunky VisualItemModel in tab view and doesn't initialize multiple times.
https://doc.qt.io/archives/qt-5.6/qtquick-performance.html
In general, "property var" should be considered to be superior to "property variant" for every use-case from QtQuick 2.0 and newer (note that "property variant" is marked as obsolete), as it allows a true JavaScript reference to be stored (which can reduce the number of conversions required in certain expressions).
