No more recursion now, but this is still slow.

We need to recompute transformGraph, I try to do this intelligently
depending on params change only.

Also, I added preservation of louvain colouring.

Also, fixed graph comparison function.

This should be both fast and more exact now (previously it only
compared node/edge list sizes, now it compares their appropriate
hashes).

Removes duplications in Reactix.purs.

This reverts commit a6ec0726.

This is because useSession wasn't working there.