Move initialization to a separate function and connect that to the
reset button.
Two points of note:
1) Reseting the text-fields causes signals. Thus, signals have to
be ignored during reset. Do this with a new flag.
2) To make reset of the from-date work, the from-date has to be
initialized to a distinct value. Setting a default-constructed
QDateTime leaves the widget unchanged.
Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>
a455b32e02