add message board page

Add a route for '/messageboard' and a corresponding messageboard view
template.

Add a controller for the message board and use it to render a (fixed for
the time being) list of messages.
connect message board list to REST service

Add a MessageBoard service to load messages from the REST services using
Angular's $http service.

Provide an Angular factory for the 'MessageBoard' service so that it can
be used by Angular's dependency injection and therefore can be injected
in the controller.
solve ambiguous name of working branch

Rename the example branch to 'impl' rather than 'solution' to remove any
ambiguity with the solution tag.

Wrap lines in the README on 100 characters.
add quick start and reorder sections

Add quick start section to the README and reorder its sections so that
explanations get more detailed towards the end of the document.