Comparing metadata vs Demokritos' schema

[josvandervelde]

Comparing our implementation with Demokritos' metadata schema.

I needed some code to make this easy. Probably we'd like to do this more often, so I figured it makes sense to make it part of this project. Still, I think it should be very separate functionality, so I placed it in a separate directory.

See README.md for how it's mean to be used.

I manually checked all the differences between our implementation and Demokritos' metadata schema. I committed this to the with_comments directory. It's nice to have that versioned, and I thing it's not abusing this repo too much to put it here.