fixing copy paste error in copyright blurbs
adding ctags rule to Makefile.am
Adding auto keyword to parser for automatic prefixes

This commit adds the auto keyword to signal radvd that the prefixes for
and interface should be determined automatically.  Each automatic prefix
definition may expand into multiple prefixes, so the AdvPrefix structure
has also been updated to contain a list of prefixes rather than just one.
Add loops around the PrefixLists