Document raster commands, old and new.

[wdconinc]

I know its been written somewhere and I should know it, but a catalog of the existing, and previously used definitions of raster (i.e. /remoll/oldras true or false, and this new version of raster macro commands) and what they do (and which generators they worked in) would be appreciate.

For reference, can this be verified as at least not wrong, I am using for envelope production: /remoll/oldras false /remoll/rasx 5 mm /remoll/rasy 5 mm /remoll/evgen/set moller

Originally posted by @cameronc137 in https://github.com/JeffersonLab/remoll/issues/213#issuecomment-468351342

[rahmans1]

@cameronc137 Just to comment on this. I have always used /remoll/oldras true for all my studies. I have never looked deep into the code to see what it does. But to my understanding of the old master branch, if oldras is set to true, the particles are not generated with raster angle correlations for the moller generator. It was also the default behavior. I didn't completely trust the implementation of the raster angle correlations in that branch. So, I have always used oldras true. 1) To summarize, the default behavior in beam generator now has raster angle correlations. So, you technically don't need to use the macro to set it. 2) The default behavior in the old master branch had no raster correlations. And if u set it to false, u would get raster correlations which may or may not be correct. If nobody has worked on it since then, that should be the same issue in current develop.

Hope that gives some clarity.