This introduces the `--clone-from-file` option for
solana-test-validator. It allows specifying any number of files
(without extension) containing account info and data, which will be
loaded at genesis. This is similar to `--bpf-program` for programs
loading.
The files will be searched for in the CWD or in `tests/fixtures`.
Example: `solana-test-validator --clone-from-file SRM_token USD_token`
* Move test-validator to own module to reduce core dependencies
* Fix a few TestValidator paths
* Use solana_test_validator crate for solana_test_validator bin
* Move client int tests to separate crate
Co-authored-by: Tyera Eulberg <tyera@solana.com>