Implement caching of local DOFs in bind.

We originally wanted to implement this cache but never did this. I implemented a benchmarking computing the L^2 norm of FE function with Lagrange-DG basis and various order for the DG space and the quadrature rule.

It turned out that caching is neven harmful (even for low order). But it may lead to minor improvements (up 10%) if the quadrature order (and thus the number of local evaluations) is large.

A side effect of this change is, that using proxy or on-the-fly containers will no longer work. Hence this needs to be discussed before merging.