QmlDesigner.PropertyEditor: There is no passwordMode on TextField

Change-Id: I7b8c9ea09ace69f66f8fd1cc5128d92418250fde
Reviewed-by: Marco Bubke <marco.bubke@digia.com>
QmlDesigner.PropertyEditor: Fix text for CheckBoxes

We need to set the text to the value, so that the user can see which
value is explicitly set.

Task-number: QTCREATORBUG-12195
Change-Id: I0b405839122f3b008790df3e3c2b0b7728299b7a
Reviewed-by: Marco Bubke <marco.bubke@digia.com>