Start building infrastructure to automatically build and deploy the
`orangeRelease` variant to Google Play.
The variant needs an automatically incrementing `versionCode`. That is
derived from the count of all commits.
Change the separator between the version and the build metadata in the
`versionName` from `-` to `+` to be consistent with semantic versioning.
This is still an experiment, so the workflow is triggered manually and
only uploads to the internal track
Nik Clayton