Correct NCSS ServiceType string in ref doc.
Merge branch '4.5.4' of https://github.com/Unidata/thredds into 4.5.4
Merge branch '4.5.4' of https://github.com/Unidata/thredds into 4.5.4
Merge branch '4.5.4' of https://github.com/Unidata/thredds into 4.5.4