Adding ci test

[axelande]

Here is one example of how a automatic test could look like, now it is just checking on Ubuntu that the UI got the two different requirements and checking the version of the first one.

(Also added a polite message that the user needs to install pip if that is not present in the installed qgis)

[m-kuhn]

Thanks a lot for adding tests!

I have a couple of small questions/remarks which I hope will make this solid.

[m-kuhn]

Can you make sure the style test passes?
After that I think it's ok.