Merge #144

144: Improve output of the libtock test suite r=Woyten a=Woyten

This PR adds clear assertions to the integration test suite. It also tries to remove some confusion about the intent of the integration tests by renaming them from `hardware_test.rs` to `libtock_test.rs`.



Co-authored-by: Woyten <woyten.tielesch@online.de>