Integration test framework

[rajarshimaitra]

Description

Fixes #62

This PR adds a rough integration test framework that can be used to programmatically test bdk-cli with a regtest backend for different scenarios. It uses std::process::Command to execute system commands with custom arguments..

Currently it only includes build with all features, perform a basic wallet op. More tests can be added later.

The tests can be run via cargo test and it will run them in the integration test section https://doc.rust-lang.org/rust-by-example/testing/integration_testing.html

Checklists

All Submissions:

• [x] I've signed all my commits
• [x] I followed the contribution guidelines
• [x] I ran cargo fmt and cargo clippy before committing

[rajarshimaitra]

License updated..

[rajarshimaitra]

The tests are failing because there is no bitcoind running in the test environment.. This needs to be fixed..

• One way is to manually download and deploy a bitcoind binary in test env using shell commands..

• Another way is to do it using the bitcoind crate.

  Will figure which one fits better, and update..

[rajarshimaitra]

I feel the best way to go about this is merging https://github.com/bitcoindevkit/bdk-cli/pull/65. In that way we will get a automatic regtest node with bdk-cli. And we don't need to replay bitcoind actions again in the integration test..

cc @notmandatory

[rajarshimaitra]

This one is awaited on the 2nd part of #65, where RPC controls are to be exposed from bdk-cli itself. That will be the easiest way to have a fully featured test framework with backend included.. And we won't need a wrapper over bitcoin-cli anymore..

[rajarshimaitra]

This is now superseded by https://github.com/bitcoindevkit/bdk-cli/pull/92