tools: expose skip output to test runner
tools: expose skip output to test runner

In the TAP protocol, skips are flagged as ok. Expose more
information so we can understand if the test was skipped or not.

PR-URL: https://github.com/nodejs/io.js/pull/2130
Reviewed-By: Sakthipriyan Vairamani <b84950071fc99921a72f4fa56f6cad2496b3223c@gmail.com>
Reviewed-By: Ben Noordhuis <59bd0a3ff43b32849b319e645d4798d8a5d1e889@bnoordhuis.nl>

dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node