Docstring needs more detail for Bazaar Plugin Guide

bzr-testrunner is included in Bazaar's Plugins Guide (http://doc.bazaar-vcs.org/plugins/en) which uses the docstring of the plugin as its description. bzr-testrunner has a very, very terse docstring with more detail in a README file. It would be nice if some of the content of the README file also appeared in the docstring so that the help in the Plugin Guide and in ``bzr help`` could be more complete.