Added check for day-night flag as UMM granules in format other than ECHO10 could have a nil day-night flag value.
Added check for day-night flag as UMM granules in format other than ECHO10 could have a nil day-night flag value.

nasa/Common-Metadata-Repository,mschmele/Common-Metadata-Repository,mschmele/Common-Metadata-Repository,mschmele/Common-Metadata-Repository,nasa/Common-Metadata-Repository,nasa/Common-Metadata-Repository,nasa/Common-Metadata-Repository,nasa/Common-Metadata-Repository,nasa/Common-Metadata-Repository,mschmele/Common-Metadata-Repository