添加抽象工厂模式示例，包含手机和笔记本电脑的具体产品及工厂实现，并更新相关文档和构建脚本

go/Makefile

@@ -0,0 +1,28 @@
+BUILDDIR := build
+DIRS := $(shell ls -d */)
+
+.PHONY: build
+build:
+	mkdir -p $(BUILDDIR); \
+	for dir in $(DIRS); do \
+	    if [ ! -f "$$dir/main.go" ]; then \
+	        continue; \
+	    fi; \
+		pkg=$${dir%/}; \
+		go build -o $(BUILDDIR)/$$pkg ./$$dir/main.go; \
+	done
+
+.PHONY: test
+test:
+	for bin in $(BUILDDIR)/*; do \
+	    echo "\n"; \
+		$$bin; \
+	done; \
+	echo "\nAll Go examples executed.\n"
+
+.PHONY: clean
+clean:
+	rm -rf $(BUILDDIR)/*
+
+.PHONY: all
+all: build test clean