Bug 2505 - Add commented use warnings where missing in the opac/ directory

opac/changelanguage.pl

@@ -15,6 +15,9 @@
 # Koha; if not, write to the Free Software Foundation, Inc., 59 Temple Place,
 # Suite 330, Boston, MA  02111-1307 USA
 
+#use strict;
+#use warnings; FIXME - Bug 2505
+
 use C4::Output;
 use CGI;
 

opac/opac-user.pl

@@ -17,6 +17,7 @@
 
 
 use strict;
+#use warnings; FIXME - Bug 2505
 
 use CGI;