same logic when clone --noop private repos. Fixes #593
improve expectation for hub --noop clone

As suggested by @mislav, the the previous assertion only checked against
"git clone" without parameters.
fix negative assertion checking only first element

expect(x).to_not returns false when the test passes, so using history.all? only
checks the first element of the list. Since expect raises anyway, we
don't need to bother anyway.
Merge pull request #594 from lepistone/fix-clone-private-noop

Fix `git --noop clone` with private repos

Fixes #593
Merge remote-tracking branch 'origin/master' into merge_master