[OE-core] Automatically creating tar files for bin_package.bbclass

[Andre McCurdy]

Say I have a proprietary library which only I can build from source
and I have a conventional recipe which builds it within OE. I would
now like to create a tar file of the library and headers etc, plus a
companion recipe based on bin_package.bbclass to allow others to make
use of the library in their OE builds. ie the situation described
here:

  http://www.yoctoproject.org/docs/2.1/mega-manual/mega-manual.html#packaging-externally-produced-binaries

Is there a recommended way to create the tar file to support that?
e.g. a class which automatically creates a deployable tar file of a
recipe's ${D} directory?