DataFormatter didn't properly support, call out to the alternate CellFormat
instead for the formatting.
This also allows us to enable some disabled parts of DataFormatter unit tests
We still need to rationalise DataFormatter and CellFormatter though, so we
only have one set of cell formatting logic...
git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1710399 13f79535-47bb-0310-9956-ffa450edef68
