We implement a new `Element` trait which allows for more complex output
to be drawn, such as vertical and horizontal stacks.
We adapt `Table` to work within this system.
We refresh the output of `rad patch show` to use these new tools.
Make the documentation more realistic by using two peers, a maintainer
and a contributor, for the client examples. Define them as 'workflow'
examples, ordering them in their own directory to aid user navigation.
Sebastian Martinez