LinktaFlow GET and POST working with database

[relandboyle]

Description

Trees API is working with database connection for GET (search for tree by treeId) and POST (update existing tree by treeId). Some logic will likely continue to evolve. Currently, update operation overwrites an existing db entry. No versioning or history at this time.

Fixes #6

Type of change

• [ ] 🐛 Bug fix (non-breaking change which fixes an issue)
• [x] ✨ 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
• [ ] Other 🗒️ __

How Has This Been Tested?

Tests pending.

Checklist:

• [x] I have performed a self-review of my own code.
• [ ] I have commented on my code, particularly in hard-to-understand areas.
• [ ] I have made corresponding changes to the documentation.
• [x] My changes generate no new warnings.
• [ ] Any dependent changes have been merged and published in downstream modules.
• [ ] I have reviewed the Security Best Practices Document.
• [ ] I have followed the Naming Conventions Guide for my changes.
• [x] I have ensured that my pull request title is descriptive.

Additional Information: