SingleDish pipeline can now handle multiple MS's

[thomaswilliamsastro]

• SingleDish pipeline can now handle multiple MS's

Also a little general code tidy-up, to improve readability

[e-koch]

This looks good to me from reviewing the code; most of the changes being the loop over EBs that, I think, shouldn't change the other SD pipeline steps.

@thomaswilliamsastro did you hit any other snags from local testing?

And @1054 , if you also have time to look through the changes, that would be great! You have a much better understanding of the SD pipeline than I do.

[thomaswilliamsastro]

Only other thing I changed (and maybe it's not necessary) is for the imaging it'll pull the mean frequency from the concatenated MS, rather than the first one concatted. There might be a potential crash if phcenter is not defined in that function call, but from the pipeline logic it's always passed along so I didn't see it come up

[e-koch]

@thomaswilliamsastro good to merge this on? I'll need to handle rebasing for #281

[thomaswilliamsastro]

@e-koch it's rebased here, so good to merge. I guess this might end up being irrelevant with your revamp, but hey