initial source code commit

This is the initial commit of the actual source code. This includes a README file to explain usage.

In addition, the `.gitignore` file was updated to add some additional exclusions: (vim swap files, project binary)

Here are the application components:

* `main.go`: the main program, where the interactive menu system lives
* `formatter/formatter.go`: these are the output formatters
* `options/options.go`: this is the command-line flag parsing stuff
* `ring/ring.go`: the token ring calculation code

Sorry, no tests yet. :(