Fixed bug where p_numericalValue was being set when p_dataType was...

Fixed bug where p_numericalValue was being set when p_dataType was InvalidNumericLogDataType, which was inconsistent with the behavior of the program prior to the introduction of the method NameToDataType()

git-svn-id: http://subversion.wr.usgs.gov/repos/prog/isis3/trunk@2817 41f8697f-d340-4b68-9986-7bafba869bb8