Serialise unit tests

There seems to be a race in OUnit. Serialising the tests adds less than
a second to the run time, which I think we can live with for now.

Signed-off-by: John Else <john.else@citrix.com>
Merge pull request #1872 from johnelse/serialise-tests

Serialise unit tests
CP-8888: Add diagnostic stats reporting

Signed-off-by: John Else <john.else@citrix.com>
Stop stats reporter before exiting

Signed-off-by: John Else <john.else@citrix.com>