Restructure Sub

[colbych]

sub.py is getting pretty big and starting to feel unruly. I think it makes sense to make sub a folder and then put in sub-sub modules (I don't know why it is called sub but blame Mike Shay!).

I think it makes sense to have a plotting sub (for multi_color and ims) and an analysis sub (for rotate_ten and stuff).

This might be a little bit of work, but I think it would make the whole thing cleaner.