Remove all node.js copied files and use node.git as a submodule.

This involved some changes to the existing bindings. Specifically:

1) DNS lookup should return the first address it finds whether it is
IPv4 or IPv6, and not fail when IPv6 results are an empty set.
2) Stream.writeBinaryString() wtf that is
3) util.isArray now === Array.isArray, and it should return false for
Buffer instances given to it - this change was made in DynJS.