Add default transport options section to listeners chapter
Allow ranch_ssl to use DER cert/key/ca options.

The Erlang SSL library allows keys, certs and cacerts to be passed either as DER encoded binaries or in PEM encoded files. This patch allows ranch_ssl to be configured in either manner.
Allow connection processes to be supervisors
Merge branch 'ssl_listen_nofile' of git://github.com/archaelus/ranch
Use erlang.mk for the Makefile
Use ct_helper to generate SSL certificates for testing
Update Ranch to 0.8.2
Add ranch:ref() type
Fix typespecs for ranch:filter_options/3
Add ranch_tcp:opts() type
Add ranch_ssl:opts() type
Update Ranch to 0.8.3