Revert "http: don't bother making a copy of the options"

This reverts commit 06cfff93.

Reverted because it introduced a regression where (because options were
modified in the later functionality) options.host and options.port would
be overridden with values provided in other, supported ways.

PR-URL: https://github.com/iojs/io.js/pull/1467


Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>