Make GYP patches more friendly for OpenBSD and upstream, and import some ideas/fixes from OpenBSD while here.
Import patches from OpenBSD to fix Aura build, using GTK2, enable remoting, and restore firstrun patch.
Enable printing context, from OpenBSD.
Depend on Cairo if requested, from OpenBSD.
Make OpenBSD friendly.
Ensure we link against libwebpdemux (the unbundled libwebp.gyp uses compile_test.py)
Brute-force link fix for now...