- Tidying up the build matrix
- All channels has TARGET env var
- Build against this targets:
- x86_64-unknown-linux-gnu
- x86_64-unknown-linux-musl
- i686-unknown-linux-gnu
- i686-unknown-linux-musl
- x86_64-apple-darwin
- Code formating check has it's own item in the build matrix
- Prevent target re-add error from rustup
- Incorporate the TARGET env var in the `install` and `script` stage
* Rewrite integration tests in Rust.
* Improve failure output for integration tests.
* Move TestEnv to separate module.
* Remove old integration tests script.
* Re-add integration test for subdirectory.