Add myself as contributor, update docs, and add stub dunnbook plugin

Adding my self as a contributor in both the README.md and package.json

Removing the `Usage` section from the README.md and moving it on to chapter 1 and chapter 2 of `The Book of Dunn`

Creating a stubb .dunnbook plugin with `.dunnbook` trigger which accepts  `ch1` and `ch2` arguments and spits out an appropriate url.

The intention is to really flesh out the docs which should contribute to better design/architecture as well as getting more people to contribute and write plugins.

Also I want to get the .dunnbook plugin advanced enough so that it can send a user to subsections of the docs such as `#setup` etc.