Merge branch 'mdw/multi-priv'

Merge branch 'mdw/multi-priv'

* mdw/multi-priv:
  server/tests.at, t/keyring-*: New tests for key management.
  Allow different peer associations to use different private keys.
  server: Use the new kdata system.
  server/{keymgmt.c,tripe.h}: Unify public and private key handling.
  server/keyexch.c: Prefix crypto-details trace messages correctly.
  server/{keymgmt.c,tripe-admin.5.in}: Improve key-management errors.
  admin.c (a_format): New function formats token sequences to strings.

Conflicts:
	server/tests.at
	server/tripe.h