Fix bad tests for sub-BSD OS detections that resulted in sub-BSD flavors being detected but appearing that the super-BSD was not detected.
Adjustments for building tests with dynamically generated header links for modular SVN layout.
Address endian compile errors for OSX in the cases where sys/param.h was include ahead of the predef headers. The solution was to: use the OSX machine/endian.h header, and only allow a single OS to be detected at once. Test cases added for both conditions on OSX.