Slightly better breaking of unary prefix symbols.

[jordwalke]

Summary:
Before these would break like:

!!
  myFunction(
    foo,
    bar
  )

But now they break like

!!myFunction(
    foo,
    bar
  )

This is still not ideal, but it's an improvement.

Also, one downside is that now closing parens next to unary ! are not aligned to two character grid, though they are still correctly "lined up" with their function call.

let res =
  !myFunction(
     foo,
     bar
   )

However, I think that is better than what was there previously.

let res =
  !
    myFunction(
      foo,
      bar
    )

Unary minus and friends are also improved.

let res =
  -
    myFunction(
      foo,
      bar
    )

Is now:

let res =
  - myFunction(
       foo,
       bar
     )

Unary minus doesn't have any two character grid problems because there is always a space after them. It's mostly about ! and I'd say this is still an improvement.

To fix the remaining issue seems pretty invasive at the moment.

For a future improvement, I might suggest a pass that prepends unary operators to
function names in certain cases, and then running the printer as if these unary
prefixes didn't even exist (in those cases).