Revert "Check socket writability in JS Socket.send()"

This reverts commit f0127e9d.

This change was "wrong-headed" per Deuce and broke JS sends on
blocking sockets. Thanks for the help.

This fix for inifinite-wait on send() likely led to the infinite
BinkIT errors/log messages that led to commit 4dd32231.

The real fix for this problem (which can block all other timed
events from running), would be a Socket.poll() on the socket before
send in binkp.js.