support user define function

+//Add("/user",&UserController{})
+//Add("/api/list",&RestController{},"*:ListFood")
+//Add("/api/create",&RestController{},"post:CreateFood")
+//Add("/api/update",&RestController{},"put:UpdateFood")
+//Add("/api/delete",&RestController{},"delete:DeleteFood")
+//Add("/api",&RestController{},"get,post:ApiFunc")
+//Add("/simple",&SimpleController{},"get:GetFunc;post:PostFunc")
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