nrelease: Switch over to dports for all packages.
nrelease - Set dports default, add dports defaults

* Default DPORTS_PATH to /usr/dports.

* Add dports defaults for the git build to match the git we intend to
  prepackage with the installation.
pkg_radd - update to also handle dports

* Detect that dports has been installed.  dports takes priority over
  pkgsrc in this situation.

* For dports we just 'pkg install ...'.  The script also warns if the
  /usr/local/etc/pkg.conf file has not been installed.
Merge branch 'master' into gsocdrm_merger