Add bias and rmse time series diagnostic

[kevindougherty-noaa]

Closes #100. Script creates omf and oma time series that plots bias with and without bias correction and rmse. Currently only supports radiance data. Example plots here:

[JacobCarley-NOAA]

Sample plots look great. I have one minor change request --> Recommend not using red and green together on the same plot for those with color vision deficiency. You could change the linestyle between with and w/o bc (e.g. solid to dashed or dotted). Some helpful info https://matplotlib.org/stable/tutorials/colors/colormaps.html

[kevindougherty-noaa]

Here is a new updated example addressing changes you recommended @JacobCarley-NOAA

[JacobCarley-NOAA]

Line style and colors changed - awesome! Looks great.