src: fix deferred events not working with -e

Defer evaluation of the script for a tick.  This is a workaround for
events not firing when evaluating scripts on the command line with -e.

Fixes: https://github.com/nodejs/io.js/issues/1600
PR-URL: https://github.com/nodejs/io.js/pull/1793


Reviewed-By: Trevor Norris <trev.norris@gmail.com>