BUG: Find Slicer should not be done by subprojects.
BUG: Find Slicer should not be done by subprojects.

Change-Id: I2d079e54d5fa71ec3a22154fc2620c5113afeb25

KitwareMedical/ITKTubeTK,cdeepakroy/TubeTK,thewtex/TubeTK,sumedhasingla/TubeTK,KitwareMedical/TubeTK,KitwareMedical/ITKTubeTK,LucasGandel/TubeTK,LucasGandel/TubeTK,sumedhasingla/TubeTK,aylward/ITKTubeTK,LucasGandel/TubeTK,cdeepakroy/TubeTK,matthieuheitz/TubeTK,KitwareMedical/TubeTK,KitwareMedical/ITKTubeTK,thewtex/TubeTK,matthieuheitz/TubeTK,matthieuheitz/TubeTK,KitwareMedical/TubeTK,aylward/ITKTubeTK,thewtex/TubeTK,KitwareMedical/TubeTK,cdeepakroy/TubeTK,sumedhasingla/TubeTK,sumedhasingla/TubeTK,aylward/ITKTubeTK,LucasGandel/TubeTK,matthieuheitz/TubeTK,KitwareMedical/ITKTubeTK,aylward/ITKTubeTK,thewtex/TubeTK,cdeepakroy/TubeTK