* Remove rustc dependency from ed25519 and refactor a little.
* Runtime support provides more extensive test-key functionality.
* Additional APIs for ed25519 stuff.
* Extensive test for test-runtime.
* Fixes for the new test key API.
* Additional convenience for tests
* Take advantage of more convenient API.
* Redo formating.
* Remove old test identities.
* Remove boilerplate, add test.
* Refactor out unneeded code.
* Clean up algo for determining authorities.
* Remove unneeded API.
* Make `to_*` consume
* Only export keyring when testing
* Fix build & warning
* Extract Keyring into separate library.
* Add tests for Keyring and a trait-based API.
* Address grumbles.