Merge pull request redpanda-data#46 from Jeffail/feature/amqp-declara…

…tions

Refactor AMQP declarations

Revert TLS version lock

Add durable fields to AMQP input and output types

Ensure statsd prefix is always delimited

Improve statsd aggregation

Add tls config options to amqp types

Refactor processor pipeline dispatch

Add new type field to elasticsearch output

Correct metrics interfaces

Simplify the metrics interface