it seems that commit b087dd1db6 accidentially changed
gen_write_load to not use deferred client, which causes them to be slower and not
generate high load which they should, making some tests less effecitive
* Introduce a connection abstraction layer for all socket operations and
integrate it across the code base.
* Provide an optional TLS connections implementation based on OpenSSL.
* Pull a newer version of hiredis with TLS support.
* Tests, redis-cli updates for TLS support.
