updates plotting scripts
updates npred rst file
Fixed a bug in load.py for FermiVelaRegion due to incorrect filename
Adjusts the test_load scripts to account for recent changes in FermiVelaRegion files
Fixes a bug incorrectly stating units of the output of solid_angle method in image.utils
Adds new unit test for EnergyDependentTablePSF to account for new normalized_kernel method added
updates core script
updates core scritp unit tests