[FIX] addresses nan rotation matrices computed when Y contains duplic…

[hollydinkel]

Summary of changes:

• wrap skeletonization within try: + except: statement to enable respawning node. Respawning initialize.py automatically is helpful in case there is a failure to extract skeleton on the first few attempts.
• add remove_duplicate_rows() function to initialize.py. This function removes duplicate nodes in the tracking initialization result, fixing the bug shown in the image below.
• add code for detecting and segmenting a green tip when the multi_dlo param is set