net: make connect() input validation synchronous

Socket.prototype.connect() sometimes throws on bad inputs
after an asynchronous operation. This commit makes the input
validation synchronous. This commit also removes some hard
coded IP addresses.

PR-URL: https://github.com/joyent/node/pull/8180
Fixes: https://github.com/joyent/node/issues/8140


Reviewed-By: Trevor Norris <trev.norris@gmail.com>
Reviewed-By: Fedor Indutny <fedor@indutny.com>
Reviewed-By: Timothy J Fontaine <tjfontaine@gmail.com>