Switch collector registrar to use yagnats

Signed-off-by: Casey McTaggart <cmctaggart@pivotallabs.com>
Took yagnats out of the collector and router registrars,
but desperately need integration test to verify that everything is okay as we have little
confidence. however, the tests are passing.

[#61312550]

Signed-off-by: Casey McTaggart <cmctaggart@pivotallabs.com>