LP#1640255 Hatch native messaging extension

LP#1640255 Hatch native messaging extension

Replaces Hatch Websockets communication layer with browser extension-
based communication.

Hatch API remains the same with 2 notable exceptions:

1. appendItem() API call has been removed.  It did not work as designed
   and (thus far) has served no purpose.  It was originally intended for
   offline data storage, but that will probably require something a
   little smarter.

2. The printer configuration API is no more.  This will be replaced with
   an in-app configuration page.  Note, this does not prevent use of the
   printer dialog, it only means settings are not collected from the
   printer dialog.  Overhaul still in design...

Signed-off-by: Bill Erickson <berickxx@gmail.com>