Feat/link backend models

[sammyrolfe]

Description

Created files for models and services relevant to the courseflow and coursemap components, ready to allow future front end components to interact with the current backend infrastructure.

Type of change

Please delete options that are not relevant.

• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

Testing Checklist:

• Tested in latest Chrome
• Tested in latest Safari
• Tested in latest Firefox

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings

[sylvia0929]

This PR links backend models for the Courseflow and Coursemap components, addressing issue #252. It includes the creation of files for models and services, allowing future frontend components to interact with the backend infrastructure. The code follows the project's style guidelines, includes comments for clarity, and generates no warnings.

[DudeUnleashed]

This PR seem to implement the Course and CourseMap services needed for many current and future front end functionality. The services code includes everything needed for the frontend to interact with the backend, it is neat and commented where necessary.

[aNebula]

Good work this trimester @sammyrolfe - time to make your contributions 'lasting'.
Please open an upstream PR with these changes against new/course-flow branch on doubtfire-lms/doubtfire-web.