Leave everything inside #| ... |# as is

[iamFIREcracker]

Imagine you had a file that looked like this:

#|
I like quotes:

    Lorem ipsum dolor sit amet, consectetur adipiscing elit.  Nam hendrerit
    nisi sed sollicitudin pellentesque.
|#
(define hello-world ()
  (format t "Hello, world!~%"))

Feed it to lispindent and you would get back something like this (note
how the last line gets aligned to the indented _quote):

#|
I like quotes:

    Lorem ipsum dolor sit amet, consectetur adipiscing elit.  Nam hendrerit
    nisi sed sollicitudin pellentesque.
    |#
(define hello-world ()
  (format t "Hello, world!~%"))

In addition, lispindent would now assume everything needed an extra
4 space of indentation -- this does not show up in the example, because
the code is already properly indented.

Anyways, this commit tries to fix that by building a small state
machine to handle with commented out regions:

• First it waits for the # reader macro character, followed by |
  (i.e. the start marker for these commented out regions)
• Then for | -- from this moment on, everything read from the input
  stream is kept as is
• Then waits for a | character again, follwed by a # (i.e. the end
  of the region)