Collins head finder iterator should be a list instead?

[G]

I noticed some discrepancies between the 2 different traversal orders.
reversed() on line 108 returns an iterator and if it gets exhausted in the first iteration of the loop on 111, the subsequent result is incorrect.

cort/cort/core/head_finders.py

Lines 107 to 112 in 2349f03

 if traverse_reversed: 
     to_traverse = reversed(tree) 
 else: 
     to_traverse = tree 
 for val in values: 
     for child in to_traverse: 

Suggest to change from
to_traverse = reversed(tree)
to
to_traverse = list(reversed(tree) )