- Improves script robustness under a number of specific scenarios:

   - keypair generated on disk, CSR never submitted
   - keypair generated on disk, CSR submitted, cert never downloaded
     (i.e. cert matches keypair on disk)
   - keypair generated on disk, cert exists but doesn't match
   - keypair generated, CA down, CSR requires multiple resubmits until
     CA ready
   - no keypair generated, certname exists for another host

 - Additionally make improvements:

   - Verify that there is a 200 response from the masters CA as well to
     determine CA readiness to prevent:

      - Error: cannot reach CA host 'pe-puppet'
      - Error: cannot reach CRL host 'pe-puppet'

   - Under rare circumstances *any* HTTP response may not be blank, but
     may be malformed with a unparseable status code.

     In such instances, fail fast -- otherwise, the code may reach the
     end and perform a `return ""`

   - Fix a number of minor bugs in the scripts

 - See puppetlabs/pupperware#230 for details

This is in line with how puppetserver allows access to the status
endpoint, and without this the docker healthcheck cannot access the
endpoint.

 (PDB-4811) Add tk-auth to tk-metrics endpoint

 - Both docker (per moby/moby#16585) and
   Kubernetes (per kubernetes/kubernetes#2707)
   support passing environment variables with dots as config, despite
   dot not technically being supported in POSIX.

   This is necessary to be able to specify hocon array values like
   FOO.0, FOO.1, etc now that the Hocon library is updated to
   typesafe/config 1.4.1 via puppetlabs/typesafe-config 0.2.0 /
   clj-parent 4.6.11

   /bin/sh will not add such variables to the environment, but /bin/bash
   will properly expose them, so that they may be consumed by
   puppetserver and hocon.

   NOTE: ElasticSearch is notorious for passing such values, and it also
   uses the tini init system, so it served as a good design to follow:

   https://github.com/elastic/elasticsearch/tree/master/distribution/docker

(maint) Support dotted env vars in containers