added new parallelized phylotyping script and its description txt

[arnaoutleen]

As discussed in team meeting, leen tried to parallelize and speed up Jonathan's phylotypes.py script, by:

• parallelizing the pairwise distances calculations over the different workers / threads
• distributing the "groups" to calculate onto the workers based on total # of SVs in each "worker" such that we're trying to approximate all of the workers finishing at the same time
• add in an sqlite cache to continue calculating distances if something breaks in the middle