DRILL-5431: SSL Support (C++) - Add (Netty like) socket abstraction that encapsulates a TCP socket or a SSL Stream on TCP. The testSSL program tests the client connection against a drillbit by sending a drill handshake.
DRILL-4335: Apache Drill should support network encryption. NOTE: This pull request provides support for on-wire encryption using SASL framework. Communication channel covered is: 1) C++ Drill Client and Drillbit channel.