Very wild, totally WIP.

Cleanup/import on top

Move some import statements to the top of the file.

Note: This merge request includes a small bugfix. In some mysterious way an import was wrong after the last merge request. The strange thing is: I'm pretty sure I removed my build directory and tested the feature before merging. After merging and going back to master it didn't work anymore. Maybe I didn't delete the build directory but it is strange nonetheless.

See merge request !39

Feature/code restructuring

All the restructuring stuff we talked about.

Tested.

See merge request !38

refactoring pullback loopy update

This MR will supersede !34 and !27 as I created a big mess while working on those two.

See merge request !36

We do not need it.

Various fixes, including diagonal jacobian transformations.

Feature/sumfact amatrix

Create Theta matrix for sumfactorization in constructor.  This is just a starting point for further implementations.

See merge request !37