Terminate the stdout buffer before trying to print it...
Partial rework of the cheritest UI:

 - A new -a option is the prefered way to run all tests.  'all' works,
   but is deprecated.
 - Add a -l option to list all tests.  With -v it also lists the
   decription.
 - usage() no longer lists all tests so it is more useful to humans.
 - The -l option support XML and JSON output via libxo.