diffx Extension - workaround for build error.
Reverse d1ca28b7c7a9b123f98aade4f5c0340dcb225e43
(HyperLinkModel&Writer) prior to integrating Alberto's 27 May contrib.
Alberto's contrib of 27 May
Integrate Alberto contrib.
Changed name FldSimpleUnitsHelper to FormattingSwitchHelper
Use Hyperlink model/writer in HTML output.