Revert "NumberSpinner valueNode refactored to use NumberDisplay. https://github.com/phetsims/sun/issues/575"
Revert "NumberSpinner valueNode refactored to use NumberDisplay. https://github.com/phetsims/sun/issues/575"

This reverts commit 34da4fc2b7148b287c2579122c88bde8a1bbd925.

phetsims/sun,phetsims/sun,phetsims/sun