use github.com/gobs/readline and add history

Replaced your readline with github.com/gobs/readline. It works on *nix and OSX, using the standard readline libraries, with history management and stuff, and it "downgrade" to something like your original implementation on Windows (unless you install the MINGW32 version of libreadline and build with "go build -tags libreadline")

This implementation also supports command completion, so I am going to play with adding the supported methods (fmt.Println and stuff to it)