Remove warnings

* Remove assigned but not used variables (GCC 4.6)
* Bump _XOPEN_SOURCE to 600, ridding of FreeBSD warnings (this probably need
  to be tweaked on a per-implementation basis as problems arise)

WINGs/wfontpanel.c

@@ -5,6 +5,7 @@
 
 #include <ctype.h>
 #include <string.h>
+#include <strings.h>
 #include <stdint.h>
 
 #include <X11/Xft/Xft.h>