PvlKeyword.h: 2011-04-12 Steven Lambright - Lessened the memory footprint by...

PvlKeyword.h: 2011-04-12 Steven Lambright - Lessened the memory footprint by changing p_comments and p_units to pointers, p_values to a QVarLengthArray and p_name to a char *. 

git-svn-id: http://subversion.wr.usgs.gov/repos/prog/isis3/trunk@2243 41f8697f-d340-4b68-9986-7bafba869bb8