Adds initial support to @detectXSS

Libinject was recently updated to support XSS detection. This commit adds
initial support to it.

apache2/libinjection/libinjection_xss.h

@@ -0,0 +1,21 @@
+#ifndef LIBINJECTION_XSS
+#define LIBINJECTION_XSS
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * HEY THIS ISN'T DONE
+ */
+
+/* pull in size_t */
+
+#include <string.h>
+
+  int libinjection_is_xss(const char* s, size_t len, int flags);
+
+#ifdef __cplusplus
+}
+#endif
+#endif