timers: fix unref() memory leak
timers: fix unref() memory leak

The destructor isn't being called for timers that have been unref'd.

Fixes: https://github.com/joyent/node/issues/8364
PR-URL: https://github.com/iojs/io.js/pull/1330
Reviewed-By: Fedor Indutny <e39d94bae70283f13d24c278e04952d6dad9384b@indutny.com>
Reviewed-By: Jeremiah Senkpiel <f1782d15e31ad502ea2c097c21cc235811d0cb7c@rocketmail.com>

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