add makefile

Signed-off-by: Pavel Okhlopkov <pavel.okhlopkov@flant.com>

Makefile

@@ -0,0 +1,22 @@
+GO=$(shell which go)
+GIT=$(shell which git)
+
+.PHONY: go-check
+go-check:
+	$(call error-if-empty,$(GO),go)
+
+.PHONY: git-check
+git-check:
+	$(call error-if-empty,$(GIT),git)
+
+.PHONY: go-module-version
+go-module-version: go-check git-check
+	@echo "go get $(shell $(GO) list ./cmd/shell-operator)@$(shell $(GIT) rev-parse HEAD)"
+
+.PHONY: test
+test: go-check
+	@$(GO) test --race --cover ./...
+
+define error-if-empty
+@if [[ -z $(1) ]]; then echo "$(2) not installed"; false; fi
+endef