F-Race Fixes

-F-Race no longer discards all parameter configurations if the post-hoc
test fails to determine where the statistical difference lies

-F-Race now compares minProblems to the length of the results list
(not the iteration count) to determine when statistical tests should
be performed

Signed-off-by: Bennie Leonard <bennie.leonard@gmail.com>
Merge pull request #175 from benniel/f-race

F-Race Fixes