Device testing on Browserstack

As we discussed at our meeting, we would like to do some basic smoke tests of the vpn app in different devices, so we can get an initial idea of how things will look in various devices that are different from the ones we have. We wanted to do this so we wouldn't be surprised when we release and find out that a large number of devices are not working at all with design elements.

We now have an opensource licenses at Browserstack.

@cyberta could you look into how we could plug our CI pipeline into Browserstack to try and get some device testing results?

It looks like Espresso tests were added and Browserstack supports espresso, so that initial work has already been done, I think its just about gluing things together now.