Multiline comments

Like this:

```
#
  This class implements the Gettysburg Address.

  If this is called less than four score and seven years after the beginning of the universe,
  this will throw a `MuchTooEarlyException`.
#
MyClass:

    #
      This is my function.
      There are other functions like it,
      but this one is mine.
    #
    MyFunction:
       :x*x
