readcsv function without limit parameter

Redmine #5624

From Ted:
readcsv(): new function with acceptance test
(cherry picked from commit 5d73f3bc06c6a8e08013b23b96e01a573d801ac7)
Redmine#5624: add readcsv() example
Make sure there are no lingering threads when we clean up.
Add dummy_etc directory in source tarball.
remake_outputs.pl was missing from the source tarball.
Merge pull request #1772 from jimis/master

3.6.x changes missing from master.