Ta-tooling

- When fetch for student list, filter the result for only student using `courseRoleId`.
- Allow user to supply URL containing `course_id` instead of the actual `course_id`.
- Remove whitespace in the target name for makefile.
- Support directly categorize from a ZIP file.
- Add tools for extracting and downloading file submission

- Add makefile wrapper package.

- Use click instead of argparse.
- Separate cli into its own module.
- Add bbutils, an internal package.

- Open source release of a script in an internal project.