Correct C++ update + reorganizing Module bindings

[hschreiber]

For homogeneity, I would do the same for Summand and Box as a next step. Are there some methods you would like to add to the bindings of those two classes, while I am at it? (by default I will at least add __setstate__/__getstate__ for both)

Note that I added the method summands_of_dimension_range to the Module bindings (to use like for s in mod.summands_of_dimension_range(d): ...), which you could use instead of get_module_of_degree if no copy is needed.

And please verify that I didn't forgot to add the latest changes you made to the Module bindings.

Edit: Did the changes for the Summand and Box bindings in this PR in the end as it was quick.

For the changes in the AIDA.ipynb notebook, I just replaced the end of box 15 with:

if len(mma_):
    num_parameters = mma_[0].num_parameters
    mma_.box = [[0]*num_parameters,[1]*num_parameters]
    mma_.box = mp.grids.compute_bounding_box(mma_)