fixing code based on PR comments - cosmetic

Author: vikasnkumar

examples/demo.pl

@@ -93,7 +93,6 @@ sub prompt {
 );
 prompt("Area curve with filled colors");
 
-
 ################################
 # some 3d stuff
 ################################

lib/PDL/Graphics/Gnuplot.pm

@@ -5301,7 +5301,7 @@ our $cOptionsAbbrevs = _gen_abbrev_list(keys %$cOptionsTable);
 	pt => ["pointtype"],
 	ps => ["pointsize"],
 	fs => ["fillstyle"],
-	fc => ["fillcolor"]
+	fc => ["fillcolor"],
     };
     for my $k(%$officialAbbrevs){
 	$cOptionsAbbrevs->{$k} = $officialAbbrevs->{$k};