We need the transparent account privkey in order to be able to derive
the secret key for any leaf transparent address under the ZIP 316
diversified address tree.
UnifiedViewingKey had a bug that made it incompatible with ZIP 316.
For compatibility with the current `zcash/librustzcash` revision we use
a temporary fake UFVK encoding that stores sufficient information to use
the current APIs, and a superset of the actual ZIP 316 FVK information.
To quickly get this implemented, some calls in the demo-app have been wrapped in `runBlocking {}`. This is not ideal and will be addressed in followup issues.
Move SDK from the root gradle project to its own Gradle module
Move the demo app to be a peer of the SDK
This will simplify integration with CI on Bitrise.