Add some servald config set-up functions to 'testdefs_routing.sh' and
'testdefs_swift.sh' that can be re-used in the Swift Routing API tests.
Improve some commenting on existing functions, for consistency.
Consists of a single, one-shot request, GET /restful/route/all.json, for
the time being. A "newsince" request can be added later.
Add a Markdown tech doc that specifies the new Route REST API and update
the MDP tech doc a little.
Add the 'routerestful' test script, which uses some test utility
fuctions that have been factored out of the 'routing' test script into
the new testdefs_routing.sh.
Add the new 'allrestful' test script.