Adds initial support to @detectXSS

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

tests/op/detectXSS.t

@@ -0,0 +1,18 @@
+{
+   type => "op",
+   name => "detectXSS",
+   input => "",
+   ret => 0
+},
+{
+   type => "op",
+   name => "detectXSS",
+   input => "this is not an XSS",
+   ret => 0
+},
+{
+   type => "op",
+   name => "detectXSS",
+   input => "<a href=\"javascript:alert(1)\">)",
+   ret => 1
+}