Create the UX concept for the Maintenance tool

Create a UX concept which works for the installation UX.

The current user flow:

1. Open Maintenance tool
2. Sign in
3. Select: Add or Remove
4. Select Creator 14.0 to be installed (my current version is 13.0)
5. Switching Qt version to something newer
6. Click install - took 20min or more.
7. Install finished
8. I open Creator, and it is still version 13.0
9. I open Maintenance tool again and see that I had selected Creator 14, but that the installed version is 13.0
10. I close Maintenance tool frustrated and search where are all Creator versions installed. 
11. I find Version 11.0, which I have installed as a standalone at some point, and that 13.0 version. I am wondering where is that version 14.0 I waited for 20min
12. I open Maintenance tool again, and I select Update (instead of Add or Remove). I remembered that there was this weirdness. 
13. I see a listing of apps (Creator 14.0 included) to be installed. Only now I get it installed. 

To fix this:

• We need to show to the user in the tree what has been installed with some symbol, tag, or whatever works
• When selecting or deselecting items, they get updated - there should not be a second update workflow.

All in all, we need to get rid of two flows - there should only be one flow. This needs to be determined by devs if possible