put the following files here to have your apk signed by the release script
- build_tools_path.txt:
	contains one line which is the path to the build tools directory, e.g. ~/Android/Sdk/build-tools/33.0.0
- upload-keystore.jks:
	upload keystore containing the signing certificate with the alias "upload"
- password.txt:
	contains one line which is the password to the keystore
