More test case work:

 * make sure to build rsync before running 'make check'

 * Put back in the loglevel concept from the samba scripts.  If >8,
   then turn on shell tracing.

 * Allow tests to return 77 if they want to count as 'skipped'.

 * Add more docs.

 * Mangle Phil's script to get ready to run on non-Linux systems: we
   need to not use shell functions, cp -a, etc.  Not there yet.