Promote to master (#59)

* Java 6 and 7 compatibility fix (#55)

* Fix using a Java 8 method call to retain 1.6 compatibility

* Enhance documentation around managing certificates.

* Release notes for 2.4.2

* Version bump

* Remote exit issue (#58)

* Close socket, reader and writer when EXIT detected and return a message

* Do not close System.in

* New version

* Updated release notes 2.4.2