[minor] additional signing for osx to be compatible with sierra
[minor] additional signing for osx to be compatible with sierra

We want to make sure signatures are applied to the compiled binaries in
addition to the loader package.

Resolves #278

mozilla/mig,rezen/mig,mozilla/mig,jboyer2012/mig,ameihm0912/mig,rezen/mig,mozilla/mig,jboyer2012/mig,jboyer2012/mig,mozilla/mig,mozilla/mig,jboyer2012/mig,ameihm0912/mig,rezen/mig,ameihm0912/mig,rezen/mig