An alternative for normalize_uri

normalize_uri doesn't seem to work very well in our case, so
we do our own thing here.

Author: wchen-r7

lib/metasploit/framework/login_scanner/jenkins.rb

@@ -17,7 +17,9 @@ def set_sane_defaults
           self.uri = "/j_acegi_security_check" if self.uri.nil?
           self.method = "POST" if self.method.nil?
 
-          self.uri = normalize_uri(self.uri)
+          if self.uri[0] != '/'
+            self.uri = "/#{self.uri}"
+          end
 
           super
         end