UI does not update after credentials RPC on darwin

One way to fix this is to change qt4reactor to let us pass in whether we want a QApplication or QCoreApplication.
However, it seems better to try to fix this in our own code instead of worrying about patches to other code.

Another way is to move UniqueApplication up out of the controlpanel/gui/ tree.
This way it won't import all that crap it doesn't need before it can initialize the QApplication instance.
Then we can create the UniqueApplication in the toplevel script before any reactors are created.
I've done this by changing main.main() to take the app instead of argv.

I've tried this - I moved ubuntuone/controlpanel/gui/qt/uniqueapp/ to ubuntuone/controlpanel/uniqueapp, and it works on darwin, but it needs fixes for the tests in controlpanel/gui/qt/main/tests/test_main.py because I'm now passing the app to main instead of argv.

I'm noting all this before I make those test changes because I'm curious if anyone has objections to the change.
See the linked branch to see what I've done so far.

comment 1 refers to an attached branch that has been removed.

We decided on a third approach to fix this - change tcpactivation over in ubuntu_sso to avoid importing twisted.internet.reactor upon import, which breaks the cycle by letting us import UniqueApplication from where it is now without installing the default reactor. (see Bug #1017672)

Then the only change required in this branch is to move the code that installs the qt4reactor into main(), after the UniqueApplication instance is created.