1. Modified Nc4Iosp so that:
   1. It registers with NetcdfFile IF
      the flag -Ducar.nc2.jni.netcdf.Nc4Iosp is defined.
      It registers ahead of H5Iosp so that it will be used
      preferentially for .nc files.
   2. If registered, it accepts files that
      1. end with .nc
      2. has the correct "HDF" magic header in file.
   3. Looks for the environment variable JNA_PATH
      to set the netcdf.dll library path.

2. Modified cmd-test/pom.xml cdm/pom.xml to set
   the flag -Dfile.encoding=UTF-8 so that utf input/output
   is properly handled.
1. Reverted Section.java
2. Convert some (but not all) test programs
   to use thredds-test
Merge branch 'target-4.3.17' of https://github.com/Unidata/thredds into target-4.3.17