Use GitHub LSF for quadrature data

[ablech]

Including quadrature points and weights in git commits directly is not ideal, since it will blow up the size of the repository on the long run. Instead, we could use GitHub Large File Storage.

Github has a low quota for LSF, but allows to use LSF in connection with a different storage location of the files. We need to find an open access data storage for quadrature points and weights compatible with Github LSF.

Depending on the storage solution, we might also want to reconsider our storage format and to provide the quadrature data with a different license.