ci/deploy.sh: Allow non-root deploys

ci/deploy.sh: Allow non-root deploys

Currently, deploying Fuel@OPNFV requires the `ci/deploy.sh` to be ran
as root user, for:
- hypervisor access (virsh);
- installing prerequisite packages;

We can support non-root deploys if we relax above restriction into:
- current user should have hypervisor access beforehand
  (new check added);
- current user has passwordless sudo rights, for installing packages;

Later, we should move the package installation out of the deploy
script (`ci/deploy.sh`), making the whole deploy possible without
sudo, only hypervisor access.

After this change, the old way (sudo ci/deploy.sh) should work just
like it used to before, so no regression/behavior change should be
introduced with this.

Change-Id: Ib2ea96aa7b6d67ba0606318407a8adeb51e6969d
Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>