Add help to Makefile

Author: Andonome

Makefile

@@ -7,7 +7,7 @@ ifneq (,$(wildcard /usr/share/bash-completion/completions/))
   targets += /usr/share/bash-completion/completions/$(pkgname)
 endif
 
-all: build/$(pkgname) build/completions/bash build/completions/zsh build/completions/fish
+all: build/$(pkgname) build/completions/bash build/completions/zsh build/completions/fish ## All targets
 
 build/$(pkgname): cmd/*.go | build/
 	go build -o $@
@@ -27,28 +27,35 @@ build/completions/%: build/$(pkgname) | build/completions/
 	mkdir -p $@
 
 .PHONY: clean
-clean:
+clean: ## Remove generated files
 	$(RM) -r build
 
 .PHONY: uninstall
-uninstall:
+uninstall: ## Remove local installation
 	$(RM) $(targets)
 
 .PHONY: test
-test:
+test: ## Run the go tests
 	go test ./... -v
 
 .PHONY: docker-build
 docker-build:
 	docker build -t mermaid-ascii:latest .
 
 .PHONY: docker-test
-docker-test:
+docker-test: docker-build ## Run the go tests in docker
 	docker build --target test -t mermaid-ascii:test -f Dockerfile.test .
 
 .PHONY: docker-run
-docker-run:
+docker-run: docker-build
 	docker run -i mermaid-ascii:latest
 
 dev:
 	air
+
+.PHONY: help
+help:
+	@awk 'BEGIN {FS = ":.*?## "} /^[0-9a-zA-Z._-]+:.*?## / {printf "\033[36m%s\033[0m : %s\n", $$1, $$2}' $(MAKEFILE_LIST) | \
+		sort | \
+		column -s ':' -t
+