=begin/=end HEREDOC breaks preceeding newline in comments

[zzak]

Steps to reproduce:

1. start with a file (foo.rb):

=begin
  a comment with
  line
  breaks
=end

##
# an actual description for
# this
# module with
# more line
# breaks
module Foo;end

2. generate ri:

doc -o foodocs -r foo.rb

result

= Foo < Object
------------------------------------------------------------------------------
  a comment with
  line
  breaks

## # an actual description for # this # module with # more line # breaks
------------------------------------------------------------------------------
------------------------------------------------------------------------------