Write a function that finds all the preimages of a node in an almost tree

[jeffwack111]

This will be used in the following functions

• globalarms
• components
• showtree

[jeffwack111]

while !isempty(activenodes)

[jeffwack111]

the global arms application is a bit different because we are working with an undirected graph compared to the directed graph of the dynamics tree. We could orient the tree with the notion of "towards zero"

[jeffwack111]

Now that we are using dicts for Hubbard trees, what is the relevance of this issue?

[jeffwack111]

component() is doing these use cases