releaes-upgrader qt5 merge

[Jonathan Riddell]

I've merged and uploaded release-upgrader qt5 port nicely done by Harald.

https://code.launchpad.net/~kubuntu-packagers/ubuntu-release-upgrader/qt5/+merge/229620

I had to add in a few missing includes and fix for pep8 to get it happy.  

It'll need some further testing as one of the things it does before
upgrading is download a version of itself from the archive to run to
do the actual upgrade which can't easily be tested as far as I know
unless it's in the archive.

Jonathan