Create new tag.
        The function call will return 0 if the command success.

def __git_tag(git_tag):
        """
        Create new tag.
        The function call will return 0 if the command success.
        """
        command = ['git', 'tag', '-a', git_tag, '-m', '\'' + git_tag + '\'']
        Shell.msg('Create tag from version ' + git_tag)

        if APISettings.DEBUG:
            Git.__debug(command, False)

        if not call(command):
            return True
        return False