Changes

I am making the loops for the wp3 ta term (using ADG1 PDF) symmetric.
Prior to this, they ran from thermo levels 2 to nzt-2. This change
makes them symmetric by running them from 2 to nzt-1. There are
no degradations to the results as a result of this change. This
change makes it easier to generalize CLUBB's grid for both
ascending and descending grid directions. The results of this change
are BIT_CHANGING.

QuadTune: 1) Add beginnings of maps of SVD pattern, although this task is unfinished. 2) Normalize all regions by global mean, rather than normalizing each region separately.  3) Make sensitivities signed in sensitivity versus bias scatterplot.

For #910.

Add sam bv calc (#1141)

Added calculation function for SAM plots to pyplotgen for Brunt-Väisälä frequency squared
CLUBB ticket #1132 

Calculated by `N2 = g/thetav * dthetav/dz`