Add Makefile that automatically setups, runs tests and checks code style

Makefile

@@ -0,0 +1,45 @@
+PHP_BIN := php
+COMPOSER_BIN := composer
+
+COVERAGE = coverage
+SRCS = lib test
+
+find_php_files = $(shell find $(1) -type f -name "*.php")
+src = $(foreach d,$(SRCS),$(call find_php_files,$(d)))
+
+.PHONY: test
+test: setup phpunit code-style
+
+.PHONY: clean
+clean: clean-coverage clean-vendor
+
+.PHONY: clean-coverage
+clean-coverage:
+	test ! -e coverage || rm -r coverage
+
+.PHONY: clean-vendor
+clean-vendor:
+	test ! -e vendor || rm -r vendor
+
+.PHONY: setup
+setup: vendor/autoload.php
+
+.PHONY: deps-update
+deps-update:
+	$(COMPOSER_BIN) update
+
+.PHONY: phpunit
+phpunit: setup
+	$(PHP_BIN) vendor/bin/phpunit
+
+.PHONY: code-style
+code-style: setup
+	PHP_CS_FIXER_IGNORE_ENV=1 $(PHP_BIN) vendor/bin/php-cs-fixer --diff -v fix
+
+composer.lock: composer.json
+	$(COMPOSER_BIN) install
+	touch $@
+
+vendor/autoload.php: composer.lock
+	$(COMPOSER_BIN) install
+	touch $@