Better UX/UI is required for kubuntu-notification-helper

Current UX for notification helper is a bit strange and could be improved in various elements. See how it works atm. (for missing language files) here: https://www.youtube.com/watch?v=UETeERqwZ6M

What could be changed:

- we shouldn't see 2 windows when installing missing packages - if installation requires authorization, than first window for login data should be presented, than if credentials were valid, user should see second one with progress bar etc.

- if user cancel window for login data, it should just be gone and notification icon should be put back in systray. Now if we cancel first window the error message is shown and than windows are hidden but icon on systray is missing till we relogin.

- we should have list of packages that are going to be installed, now user doesn't know what packages are missing and what is going to be installed

1) The release of Ubuntu you are using

Description: Ubuntu Vivid Vervet (development branch)
Release: 15.04

2) The version of the package you are using

kubuntu-notification-helper:
  Installed: 15.04ubuntu4
  Candidate: 15.04ubuntu4
  Version table:
 *** 15.04ubuntu4 0
        100 /var/lib/dpkg/status
     15.04ubuntu3 0
        500 http://archive.ubuntu.com/ubuntu/ vivid/universe amd64 Packages