PIVOT-887: Tutorial example for using NumericSpinnerData doesn't match
what is actually required to make it work.

So, update the tutorial HTML source (spinners.xml) to match what the
actual BXML file is so users can see what really is required.

This is a merge of revision 1428056 from trunk to branches/2.0.x.


git-svn-id: https://svn.apache.org/repos/asf/pivot/branches/2.0.x@1428058 13f79535-47bb-0310-9956-ffa450edef68