Upload binary package to github releases

[clintfred]

As a (Travis) build process
I want a way to upload a binary tar.gz to github releases
so that it can be downloaded at NPM install time.

AC:

• the resultant upload can be successfully downloaded by ./node_modules/.bin/node-pre-gyp install

A good starting point might be
node-pre-gyp-github. During inital assessment this package did not upload the full archive and only created an 100 byte (correctly named) file in github.

Also note that file can only be downloaded once the release is not marked DRAFT.