proxy: add vendor module proxying-agent
proxy: add ssl proxy support
redis: connection mock broke under latest redis
config: HSM env var should be coerced to a boolean value

This is causing a collector error since the collector expects a boolean
value and instead gets a string value. The end result is the connect
method always fails if high security mode env var is set to true.
stream-sink: Explicitly ensure we release TLS slab buffer regions
cassandra: add support for node-cassandra-cql
cassandra: basic cassandra support
proxy: general release of proxy support
docs: updated for new version
release: published 1.8.0