#11 HR line support bug

[Jeffrey A. Hare]

When using dashes to insert a horizontal line, the
substitution pattern appears to be flawed.

For instance in the following:

this is a test ...

-----
=== Some Title ===
blah...

The dashed line is placed directly under the "this is a
test..." followed by a break, instead of having the break
after the paragraph and the HR above the title.

Also, if you have a list:

* item 1
** Item 2

------
=== Some Title ===

The Horizontal Rule shows up right below item 2 and
indented, rather than full width above "Some Title".

I would expect that behavior if the list were like this
instead, but this always seems to be the behavior.

* item 1
** Item 2
------

=== Some Title ===

I suspect the \n in the substitution pattern is the
culprit, even thought the comment at the end of the
line says: # ThinLine fix ##TAB