Crontab files parser

Alpha version

Usage:

toml [dependencies] cronparse = "*"

```rust extern crate cronparse;

use cronparse::crontab::UserCrontabEntry; use cronparse::CrontabFile;

fn main() { let mut crontab = CrontabFile::::new("/var/spool/cron/kstep"); for entry in crontab { println!("{:?}", entry); } } ```