Function is public.
        Create a tag for current commit / branch.
        :param deploy_tag:
        :return:

def tag(self, deploy_tag=''):
        """
        Function is public.
        Create a tag for current commit / branch.
        :param deploy_tag:
        :return:
        """
        if APISettings.SECURE_TAGGING and deploy_tag == APISettings.GIT_ACTIVATE_PRE_TAG:
            if self.check_existens_of_staging_tag_in_remote_repo():
                pass
            else:
                Shell.fail('SECURE TAGGING is TRUE! That means, before you are able to create a production tag, ' \
                           'you need to deploy the software on a staging envirnment.')
                return False
        if self.__git_tag(self.create_git_version_tag(deploy_tag)):
            return True
        return False