ENH: Mark BSplineWarping2Test as RUNS_LONG.

To clear up the

  RogueResearch6 Mac10.9-clang-dbg-x86_64-static

dashboard build.

Change-Id: I04b56308adee060dbfad064faea5f7f769bd5844
Merge topic 'BSplineWarping2TestRunsLong'

bcdf0304 ENH: Mark BSplineWarping2Test as RUNS_LONG.