implicitly add eldest key to tracked keys, in addition to "pgp_keys"
implicitly add eldest key to tracked keys, in addition to "pgp_keys"

Old tracking statements are missing the "pgp_keys" section, which makes
the client think that no keys are tracked, and that the eldest key is
new. Fix that.

keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client