some changes to pspec_redmult_cov_gps.py

Updated NDAY parameter for 64 ant obs - pre rescued data.
Updated g parameter (g = 0.2 -> g = 0.1) for 64 ants. Needed for
the 11, -11 sep's.
Some misc plotting plots. May or may not be useful.
Fix up ways bls are separated out.
Also make sure have  3 or more unique baselines, otherwise get 0 divides.
separate out sep2bl into a function.