Update make build tasks

Makefile

@@ -3,11 +3,13 @@ export PATH := ./node_modules/.bin/:$(PATH):./bin/
 PACKAGE = asyncjs
 REQUIRE_NAME = async
 NODE = node_modules/babel-cli/bin/babel-node.js
+UGLIFY = node_modules/.bin/uglifyjs
 XYZ = node_modules/.bin/xyz --repo git@github.com:caolan/async.git
-BROWSERIFY = node_modules/.bin/browserify
 
-BUILDDIR = dist
+BUILDDIR = build
+DIST = dist
 SRC = lib/index.js
+SCRIPTS = ./support
 
 all: lint test clean build
 
@@ -16,6 +18,7 @@ test:
 
 clean:
 	rm -rf $(BUILDDIR)
+	rm -rf $(DIST)
 
 lint:
 	jshint $(SRC) test/*.js mocha_test/* perf/*.js
@@ -25,18 +28,24 @@ submodule-clone:
 	git submodule update --init --recursive
 
 build-bundle: submodule-clone
-	$(NODE) scripts/build/modules-cjs.js
-	$(NODE) scripts/build/aggregate-bundle.js
-	$(NODE) scripts/build/aggregate-cjs.js
+	$(NODE) $(SCRIPTS)/build/modules-cjs.js
+	$(NODE) $(SCRIPTS)/build/aggregate-bundle.js
+	$(NODE) $(SCRIPTS)/build/aggregate-cjs.js
 
+build-dist:
+	mkdir -p $(DIST)
+	cp $(BUILDDIR)/async-bundle.js $(DIST)/
+	$(UGLIFY) $(DIST)/async-bundle.js -mc \
+		--source-map $(DIST)/async-bundle.min.map \
+		-o $(DIST)/async-bundle.min.js
 
-build: build-bundle
+build: clean build-bundle build-dist
 
 .PHONY: test lint build all clean
 
 .PHONY: release-major release-minor release-patch
 release-major release-minor release-patch: all
-	./support/sync-package-managers.js
+	$(SCRIPTS)/sync-package-managers.js
 	git add --force *.json
 	git add --force $(BUILDDIR)
 	git commit -am "update minified build"; true