Updating documetation and code comments
Still a few bugs remained.  Mostly inconsistencies about where different routines were expected to begin and end segment information and which routines were to insert how far.  The result was an occasional missed or duplicated node in the result cycle.  There was also an issue with not clearing the final stack contents when returning to node 0.  What was previously checked in worked fine when the callstack that wound back to vertex 0 was only one frame deep by then, which is unrealistic in a general case.
Cleared a regression when generating a shortest path and more than one outbound route to consider.  The path updates were happening by modifying an existing path record instead of each happening independently in its own record, hence some crazy long and illegal paths got generated once the test graph grows to a sufficient size.  The answer is to maintain path extension in get_path_between() by using Array.concat() instead of Array.push().