Closes#326
Implements loading checkpoints from the bundle the same way the android SDK does.
* Add checkpoint files
* Add checkpoint files as resources to package
* Remove stencil files
* Update wallet birthday methods to use bundled checkpoints
* [clean up] Fix test build failure
* Add Cocoapods support
* Fix for behaviour across SPM and Cocoapods
* Add test for checkpoint retrieval
* Use latest GRPC v1.x
* update checkpoint files to match android sdk
dh-ecc
Daniel Haight