Adds FromStr implementations for the std::net type wrappers

[joebb97]

Saves from having to do

impl ServerSettings {
    fn default_bind_address() -> SocketAddr {
       "127.0.0.1:8080".parse::<std::net::SocketAddr>().unwrap().into()
    }
}

Instead we can just do

impl ServerSettings {
    fn default_bind_address() -> SocketAddr {
       "127.0.0.1:8080".parse()
    }
}