feat(router): customize health-check route and add SSL redirect

I pulled #2781 and #2782 into the same PR so they'd be easier to test. This also enabled me to refactor the default route for both the healthcheck endpoint and SSL redirect into the same config block, cleaning up the config and ensuring they apply to everything (i.e. before the controller, builder, store-gateway, or app routes are processed). 

TESTING: add an SSL cert, enable SSL redirects, change the custom health-check endpoint, and ensure nothing is broken
@johanneswuerbach Mind supplying a gist or taking over this PR? I took this over to test and merge, but it sounds like we have a few changes left to make.