Fixed 2 memory leaks in production code and a few in testcases. As a
result leak_check_at_exit ASAN option does not need to turned off for
non-gui tests.
Smart pointers should be used elsewhere for consistency, but the sooner
this fixes are delivered, the lesser memory leaks are introduced.
Use of messageWidget for displaying parser status messages
setRootGroup assigns the right label to the root db folder
test uses portable QTemporaryFile instead of hardcoded file