Function tag_create 

pub fn tag_create<W: Write>(
    wok_config: &Config,
    umbrella: &Repo,
    stdout: &mut W,
    tag_name: &str,
    sign: bool,
    message: Option<&str>,
    all: bool,
    include_umbrella: bool,
    target_repos: &[PathBuf],
) -> Result<()>

Create a new tag in repositories