chore: Significantly restructure folder layout

This moves the various projects from "type-based" folders (such as
"services" or "tools") into more appropriate semantic folders (such as
"nix", "ops" or "web").

Deprecated projects (nixcon-demo & gotest) which only existed for
testing/demonstration purposes have been removed.

(Note: *all* builds are broken with this commit)

ops/infra/dns/import

@@ -0,0 +1,11 @@
+#!/bin/sh
+set -ue
+
+# Imports a zone file into a Google Cloud DNS zone of the same name
+readonly ZONE="${1}"
+
+gcloud dns record-sets import "${ZONE}" \
+       --project composite-watch-759 \
+       --zone-file-format \
+       --delete-all-existing \
+       --zone "${ZONE}"