Function lazy_conf::config

pub fn config<I, S>(c_loc_flag: &str, c_locs: I) -> Result<GetHolder, LzErr>where
    I: IntoIterator<Item = S> + Debug,
    S: AsRef<str>,

create a config loader object, so each individual config item can be built up and help items can be added too. fails if user provided flag for c_loc_flag, but it was badly formed.