Issue title: Visual Studio UDUINTS dependency
 Issue body: the latest UDUNITS fails to build with Visual Studio

open issue

https://github.com/Unidata/UDUNITS-2/issues/79

must either wait for fix or build NCO without UDUNITS
 Comments: 
 Comment 0: UDUNITS  builds using the latest release (git checkout /tags/v116.69.203.115)
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