Fix podofo 0.9.3 faillilng with test file

Use a slightly different test file
Implement v2 codesigning for the calibre app bundle on OS X

calibre is now built on 10.9.5 as that is the only version of OS X that
supports v2 codesigning. v2 codesigning is required for Gatekeeper on
all versions of OSX >= 10.9.5