Partially to learn how, partially to maintain a consistent style, and partially to see where we can improve.

As for the POSIX parser specifically, I love grammars, and want to support multiple, and building one in LALRPOP is t too bad. Also I looked at conch-parser, but didn't want to use its AST, and decided to go this route.

I have been using the termion crate, and may have another PR to contribute. I have somewhat ambitious goals for the readline like library though.