Add an export for unit tests

[lesquoyb]

Is your request related to a problem? Please describe.
I thought it could be a nice enhancement and probably not that hard to make to be able to export the summary of unit tests as a text file to make easier comparisons or just look in depth into it as the testview itself is quite painful to manipulate (because of #159 but also because of the weird display and all the menu to fold/unfold)

Describe the improvement you'd like
Add a button that would open a dialog to save the summary of unit tests into a text file on the testview

[lesquoyb]

I tested it on windows and after I pick a folder nothing is happening. I have no message in the eclipse console either