streams: update .readable/.writable to false

These properties were initially used to determine stream status back in node v0.8 and earlier. Since streams2 however, these properties were always true, which can be misleading for example if you are trying to immediately determine whether a Writable stream is still writable or not (to avoid a "write after end" exception).

This is #1217 targeting the master branch and with a couple of minor changes to fix a lint error and to help address a concern about .on().