Function certify::generate_cert

pub fn generate_cert<'a>(
    ca: &CA, 
    domains: impl AsRef<[&'a str]>, 
    country: &str, 
    org: &str, 
    cn: &str, 
    pem_str: Option<&str>, 
    is_client: bool, 
    days: Option<i64>
) -> Result<(String, String), CertifyError>

generate cert signed by the CA