Summary:
Ref T6741. Ref T10246.
Root problem: to provide Drydock in the cluster, we need to expose Almanac, and doing so would let users accidentally or intentionally create a bunch of `repo006.phacility.net` devices/services which could conflict with the real ones we manage.
There's currently no way to say "you can't create anything named `*.blah.net`". This adds "namespaces", which let you do that (well, not yet, but they will after the next diff).
After the next diff, if you try to create `repo003.phacility.net`, but the namespace `phacility.net` already exists and you don't have permission to edit it, you'll be asked to choose a different name.
Also various modernizations and some new docs.
Test Plan:
- Created cool namespaces like `this.computer`.
- Almanac namespaces don't actually enforce policies yet.
Reviewers: chad
Reviewed By: chad
Maniphest Tasks: T6741, T10246
Differential Revision: https://secure.phabricator.com/D15324
