(TK-2) Port config to prismatic schema

This commit adds prismatic schema definitions and tests for all
of the objects making up the jetty9 configuration, removes the
old configuration functions, and simplifies some of the state relating
to handlers.
(TK-2) Reorganize core namespace

This commit doesn't contain any code changes; it simply re-orders
the functions and adds some pragmas to try to make things a bit
more organized.