(#2150) Add routes file for indirector

Puppet[:route_file] is a YAML file specifying the termini to use for various
indirections, in the format:

agent:

catalog:
  terminus: rest
  cache: yaml

master:

catalog:
  terminus: compiler
  cache: active_record

This file is optional, and will override application defaults set in "setup",
as well as terminus settings, ie. facts_terminus.

Paired-With: Jesse Wolfe