Implement a skeleton for GCSFileSystem. All functions would return Status::NotImplemented(). This will keep the future changes smaller, and allow me to verify all CI builds are working in a smaller PR.

Reporter: Carlos O'Ryan / @coryan
Assignee: Carlos O'Ryan / @coryan

Related issues:

• [C++] Add filesystem / IO implementation for Google Cloud Storage (is a child of)

PRs and other links:

• GitHub Pull Request #11331

_{Note: This issue was originally created as ARROW-14222. Please see the migration documentation for further details.}