Sign the application

[iffy]

For testing, this works:

pip install humancrypto
humancrypto rsa create-private /tmp/foobar.key
humancrypto rsa self-signed-cert --common-name foobar /tmp/foobar.key /tmp/foobar.crt
openssl pkcs12 -export -out /tmp/foobar.pfx -inkey /tmp/foobar.key -in /tmp/foobar.crt -passout pass:foobar
export CSC_LINK="/tmp/foobar.pfx" CSC_KEY_PASSWORD="foobar" CSC_IDENTITY_AUTO_DISCOVERY="false"
build --win --mac --linux --ia32 --x64