while testing on osx, it seems that it doesn't support nanoseconds so it
fails this check because the mockFsEval returns the nsec precision, but
the actual expected results is:
"old": "1337888911.288518233"
"new": "1337888911.000000000"
Ideally there will be a way to detect when the fs supports nsecs
Signed-off-by: Vincent Batts <vbatts@hashbangbash.com>