Commit a5862a0 made the linking step in update_loop_data unecessary
because the loop's copy of the data was made to come from the parent
loop's data rather than the original client's data.
While at it, also add one more nested loop test case.
* Fix for issue #80
When updating the `opening_chars`, line_statment was forgotten. So, a
change to any of the openers would cause line statements to start being
unrecognized.
I added a unit test to cover this case.
* fix indentation
* add update to single_include
