add https support to use git-review to push to gerrit itself

[David Ostrovsky]

Gerrit does not use ssh. That why git-review can not be used to push to gerrit itself atm.

As it stated in SUBMITTING_PATCHES in gerrit tree:

Ensure you have obtained a unique HTTP password to identify yourself:

  https://gerrit-review.googlesource.com/#/settings/http-password

Push your patches over HTTPS to the review server, possibly through
a remembered remote to make this easier in the future:

   git config remote.review.url https://gerrit.googlesource.com/gerrit
   git config remote.review.push HEAD:refs/for/master

   git push review

You will be automatically emailed a copy of your commits, and any
comments made by the project maintainers.