Add https protocol support to clone git repositories

[MarcoRuzzon]

Who are we doing this for?

What are we building?

Why are we building this?

Is it related to a bug or problem? If so, please describe

How will the outcome be tested?

Anything else to add?

[MarcoRuzzon]

As @alaurenzi and I discussed we could start relying on a fallback strategy, if ssh fails then fall back to https protocol. This would mean that the user could be prompted for passwords "unexpectedly" (instead of build failure).