Add makefile for generate codes

Makefile

@@ -0,0 +1,34 @@
+.SILENT :
+.PHONY: docs
+
+
+GO=$(shell which go)
+GOMOD=$(shell echo "$${GO111MODULE:-auto}")
+
+
+MDs=apis.md \
+	chat_info.md \
+	dept_info.md \
+	external_contact.md \
+	media_upload.md \
+	oa.md \
+	rx_msg.md \
+	user_info.md
+
+help:
+	echo "make errcodegen | sdkcodegen"
+
+docs:
+	$(info docs: $(MDs))
+
+generate:
+	GO111MODULE=$(GOMOD) $(GO) generate ./...
+
+errcodegen:
+	GO111MODULE=$(GOMOD) $(GO) run -tags=sdkcodegen ./internal/errcodegen errcodes/mod.go
+
+sdkcodegen:
+	for name in $(MDs); do \
+		echo $${name}; \
+		GO111MODULE=$(GOMOD) $(GO) run -tags=sdkcodegen ./internal/sdkcodegen docs/$${name} $${name}.go ; \
+	done