Datalight

- Fix bug in newer versions of PyQT
- Fix PyQt version to 5.12 in requirements

Changed upload to use newer API endpoint for uploading files of unlimited size.

Add get_status function to main.py

This returns a boolean to determine whether the user has correctly set up their API key and is able to connect to the data repository.

Release for integration with Matflow

Has most features, gui is working. Can also use upload_record function directly from main.py

Basic upload functionality in place through main.py.
No metadata templates yet provided.