Extended subset graph

subset graph can now calculate all minimal included subsets
Well, it is always the first contained bitset when traversing all leafs (you can skip the branch if you found the first contained subset in that branch). However, there is another problem:
Consider the bitsets "1, 2, 3" and "2, 3". When traversing for the leaf "1, 2, 3", "2, 3" is not found because the "1" bit is the smallest bit and, therefore, is traversed first. This is the reason for a breadth first search pattern.