remove go routine for sending dnstap message from policy plugin (#101)
remove go routine for sending dnstap message from policy plugin (#101)

- go routine doesn't increase performance (neither latency nor QPS)
yuewko/themis,johnbelamaric/themis,infobloxopen/themis,johnbelamaric/themis,yuewko/themis,vasili-v/themis,infobloxopen/policy-box,vasili-v/themis