2017-04-04, Version 4.8.2 'Argon' (Maintenance)

This is a maintenance release to fix a memory leak that was
introduced in 4.8.1.

It also includes an upgrade to zlib 1.2.11 to fix a number of low
severity CVEs that were present in zlib 1.2.8.

http://seclists.org/oss-sec/2016/q4/602

Notable changes:

* crypto:
  - fix memory leak if certificate is revoked (Tom Atkinson)
    https://github.com/nodejs/node/pull/12089
* deps:
  - upgrade zlib to 1.2.11 (Sam Roberts)
    https://github.com/nodejs/node/pull/10980