Trn 126

The content of the ticket is (https://jira2.iparadigms.com/browse/TRN-126)

Although we don't currently intend to store our response data inside walker, it would make walker far more useful to a broad audience and should greatly help project adoption. It should also be very easy to implement.
Basically:
Add a config flag datastore.store_response_body, false by default
Add a column body to walker.links
If the flag is true, have cassandra.Datastore store the response body in that text column
Since this could be important to others, update the README to note that Walker can do this
Since potential users will be looking primarily at this class when implementing their handlers, could we briefly mention the config parameter that controls this? Ideally they should see it in walker.yaml but since it could fail silently (i.e. "why is the body always empty?") I think it would be a good idea to mention it.