* Add fallible send methods, and rpc_client helper
* Add helper to return RpcClient url
* Implement BenchTpsClient for TpuClient
* Add cli rpc and identity handling
* Handle different kinds of clients in main, use TpuClient
* Add tpu_client integration test
* Add BenchTpsClient
* Impl BenchTpsClient for used clients
* Use BenchTpsClient in do_bench
* Update integration test to use faucet via rpc
* Support keypairs from file that are not prefunded
* Remove old perf-utils