R1:64cc4fe91515

Add a test to verify that all routing maps are plausibly valid, and remove some dead routes

Summary:
Previously, see D20999. See also <https://discourse.phabricator-community.org/t/the-phutil-library-phutil-has-not-been-loaded/3543/>.

There are a couple of dead "Config" routes after recent changes. Add test coverage to make sure routes all point somewhere valid, then remove all the dead routes that turned up.

Test Plan: Ran tests, saw failures. Removed dead routes, got clean tests.

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