Interactive Segment Tubes: Add drop seed button

This button controls the seed dropping. Since in the interface we don't see
the drop seeds icons anymore (the one in the toolbar), we need to add one
here specifically.
Interactive Segment Tubes: Drop seeds when running the segmenter
Merge branch 'InteractiveSegmentTubes_AddDropSeedsButton'

* InteractiveSegmentTubes_AddDropSeedsButton:
  Interactive Segment Tubes: Drop seeds when running the segmenter
  Interactive Segment Tubes: Add drop seed button
Welcome Interface: Go to the module directly on double click
Bump TubeTK - Fix tube display
Fix Unix compilation
Welcome Interface: Remove transition from modules to modules & description
Welcome Interface: Add kitware logo
Welcome Interface: Correct typo
Welcome sceen: Add Kitware description text and refactor logo

Bring the logo to the new sharper vesselview style