Consistent space usage of list-construction versus list-comprehension

[lspitzner]

This looks a bit strange:

-- brittany --columns 30
foo =
  [ [1, 2]
  , [ 3 | True ]
  , [4 .. 5]
  ]

#104 discussed spaces in lists before, but did not consider (single-line) list comprehensions.

I am not sure yet what we want here. We could keep it inconsistent, or change to either [ 1, 2 ] or [3 | True].