[21pt] Create eval plots tool for ras2fim V2

[RobHanna-NOAA]

Create tools to "eval plots" for ras2fim V2. Much of the FIM eval plots tool can likely be used. The one difference is that the folder pattern that ras2fim uses for gval metrics files are very different but not the contents of the metrics files.

Some designs decisions will be need as ras2fim V2 is unit centric and not full BED centric.

It needs the ability to use one unit and compare multiple versions of that unit (aka.. v2.0.0 against v2.1.0, etc) AS well as some rollup tools to compare against other units. ie) if a new code version comes out, how did it affect all ras2fim units. Most of this is a matter of rollups and figuring different ways to feed that combinations of params into the new tool. That arg system is where most new design decisions are needed.

[RobHanna-NOAA]

A very rudimentary version is now been added via PR 320 but the tool needs to be completed.