make --minimize work again - remove menu kludge

changes in several places to allow the --minimize command line
flag to work, i.e. avoid de-iconifying during startup.
re the menu kludge, step 1, confirm it's still needed, I wasn't
able to reproduce the problem it was supposed to fix in Ubuntu 14.04
step 2, if it's still needed, try using
...menuBar().setNativeMenuBar(False) instead, I think that's the
correct fix