Changed custom shunit2 --

I have modified my customised shunit2 script so that it automatically deals
with zsh.  This means that I can just run '«shell» shunit2_pjk.sh «test script»
even if «shell» is zsh.  I assume there is a good reason why the original
script doesn't do the same thing itself, but I don't have time to explore that
now.  At the moment, my modification works for my use case.
Updated test scripts --

I have modified all of my test scripts to use the simpler methodology of
calling '«shell» shunit2_pjk.sh «test script».  Each test script now has a
simpler structure that just checks if PROJECT_HOME is set, and then sources the
script to be tested as a path from PROJECT_HOME.  No more sourcing shunit2, and
no more special setting up for zsh.
Modified test scripts --

I forgot to save a couple of edited test scripts before committing them --
fixing here.
Updated test suite script --

I updated the test suite script to suit the new test script formats.
Updated test suite script --

I made minor changes to the test suite script to make it more consistent with
my other scripts.