Allow NcML with https in URI

[lesserwhirls]

Enable the use of https in the URI for the NcML namespace when reading NcML files.

For example, this works as it should:

<netcdf xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2">

but this fails:

<netcdf xmlns="https://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2">

with the following:

Exception in thread "main" java.lang.IllegalArgumentException: Incorrect namespace specified in NcML= https://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2
   must be=http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2
        at ucar.nc2.ncml.NcMLReader.readNetcdf(NcMLReader.java:489)
        at ucar.nc2.ncml.NcMLReader._readNcML(NcMLReader.java:456)
        at ucar.nc2.ncml.NcMLReader.readNcML(NcMLReader.java:256)
        at ucar.nc2.ncml.NcMLReader.readNcML(NcMLReader.java:206)
        at ucar.nc2.dataset.NetcdfDataset.acquireNcml(NetcdfDataset.java:1081)
        at ucar.nc2.dataset.NetcdfDataset.openOrAcquireFile(NetcdfDataset.java:723)
        at ucar.nc2.dataset.NetcdfDataset.openFile(NetcdfDataset.java:572)
        at ucar.nc2.NCdumpW.print(NCdumpW.java:251)