=tcp #15766: Workaround for Windows to detect TCP abort

Nasty workaround that makes Windows report connection aborts without needing to register an OP_READ *after* the abort (which basically implies that OP_READ needs to be provided peridodically)

- [X] Allow this behavior to be overridable (i.e. settings on | off | auto)
- [X] Test on Windows 8
- [X] Test on Windows 7
- [X] Test on Build server
- [X] Test on Java 6
- [x] Test on OSX
I would prefer:

    case "auto" ⇒ Helpers.isWindows
    case _ => getBoolean("windows-connection-abort-workaround-enabled")

to ensure consistent parsing, and error reporting of boolean config setting