STYLE: fix warnings about signed/unsigned mismatches

git-svn-id: http://svn.slicer.org/Slicer4/trunk@22285 3bd1e089-480b-0410-8dfb-8563597acbee
ENH: 3228. Added preset parameters to TractographyInteractiveSeeding module for compatibility with Slicer3 Fiducial Seeding and Slicer3 Labelmap Seeding. 

git-svn-id: http://svn.slicer.org/Slicer4/trunk@22286 3bd1e089-480b-0410-8dfb-8563597acbee