Added GCOM Backend KML logic

[ghost]

Added the endpoints and objects needed to store the coordinates for KML generation. Also added tests

Description

Added the urls and models to support KML file generation on the frontend

Resolves #63

Type of change

What types of changes does your code introduce to this project?
Put an x in the boxes that apply

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update (if none of the other choices apply)

How Has This Been Tested?

Please describe the tests that you ran to verify your changes.

• Ran act on local machine to verify the model can be initialized properly
• Tested frontend to make sure it receives info from backend

Checklist

Put an x in the boxes that apply. You can also fill these out after creating the PR. This is simply a reminder of what we are going to look for before merging your code.

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules