* Refactor tests: add utils.rs for test helper functions
* Refactor sending
* Add SilentPaymentAddress struct
* Use structs instead of tuples as func arguments
* Change create_outputs function and remove amounts
* Use is_testnet in SilentPaymentAddress struct
* Provide pre-computed tweak data to create_outputs function
* Git rebase main
* Provide ecdh shared secret as argument to create_output
* Rename create_outputs -> generate_recipient_pubkeys
* Remove all references to input.rs from other files
* Move test vector test to integration test folder
* Move test vector file into integration test folder
* Move input.rs to tests folder
cygnet