Specmatic

Improvements to running asgi apps in tests.

Fixed bugs which occurred when running all tests together which have ASGI apps.
ASGI apps will be run in a separate process.

- Removed mandatory from project_root param.
Either of project_root, contract_file_path, or specmatic_json_file_path needs to be supplied

- Added support for running ASGI apps like Sanic.
- Modified the app_server creation api to make it consistent with the stub.

- Made stub_host and stub_port optional.
- Specmatic stub will run on whatever port is determined by the java package ( which is 9000 by default)
- If app_host, app_port are not supplied, the app will be run on a random freely available port.
- Added tests to illustrate explicit and implicit port settings.
- Changed the api to make it consistent with the agreed upon spec.