chore: add Makefile and Drone pipeline

Build, test, run, install and clean targets, with the version
injected at link time. CI runs make check, build and test.

Makefile

@@ -0,0 +1,38 @@
+VERSION      := $(shell git describe --tags --always --dirty 2>/dev/null || echo dev)
+GOPATH       := $(shell go env GOPATH)
+LDFLAGS      := "-X 'main.version=$(VERSION)'"
+DIST_LDFLAGS := $(LDFLAGS)" -s -w"
+
+export GOPRIVATE=coopcloud.tech
+
+all: format check build test
+
+run:
+	@go run -ldflags=$(LDFLAGS) .
+
+install:
+	@go install -ldflags=$(LDFLAGS) .
+
+build-dev:
+	@go build -v -ldflags=$(LDFLAGS) -o cctuip-dev .
+
+build:
+	@go build -v -ldflags=$(DIST_LDFLAGS) -o cctuip .
+
+clean:
+	@rm -f cctuip cctuip-dev
+	@rm -f '$(GOPATH)/bin/cctuip'
+
+format:
+	@gofmt -s -w .
+
+check:
+	@test -z $$(gofmt -s -l .) || \
+	(echo "gofmt: formatting issue - run 'make format' to resolve" && exit 1)
+	@go vet ./...
+
+test:
+	@go test ./... -cover -v
+
+loc:
+	@find . -name "*.go" | xargs wc -l