* Add documentation for operational node upgrades
* Add documentation for operational node upgrades
* Address review comments
* Some additional detail added after Richards comments
* Restructure page to make more logical sense
* ENT-2017: update ha guide to include warning about SMB 3.0 and OS incompatibilities
* ENT-2017: address PR comments
* ENT-2017: replace old ha guide references with new ones
* Extend unit test on RPCSecurityManager
* Fix corner cases in permission parsing and bug in tryAuthenticate
* Rework docsite page
* Add missing ChangeLog entry
* Add support for external data source of access control data (RPC/Shell users credential and permissions), with optional in-memory caching.
* Support password encoded with Apache Shiro fully reversible Modular Crypt Format.
* Introduce 'security' field in Node configuration and related docsite page.