MaterialsProject parser + metadata improvements

We now have a parser for Materials Project workflow data, and there is also a lot of data that could be uploaded to the beta deployment. Before this, we should do a few improvements in order to make this data more findable and also cross-linked back to Material Project.

• The parser should add some basic methodology information. This could be as simple as adding a results.method.method_name = "DFT", but it would be even better if we can also add a more detailed DFT methodology. Maybe all MP workflow uses the same XC functional etc. and we can have it hardcoded? Or then we retrieve the methodology from some external source (another NOMAD archive, MP API call, etc.)
• The entries should be tagged with external_database = Materials Project. I think currently this is done by adding a configuration document (nomad.json?) in the upload folders which determines the origin.
• In the entry overview page we need to add a link back to the Material Project website. For now, we simply reference the corresponding Materials Project material page which contains all the same data.
• We should prepare a CLI function for creating and updating the materials project workflow data by using their API.
• We should prepare a single upload containing a subset of the workflow data. Once we have improved the parsing of the data we could eventually even include the whole dataset.