Merge pull request justjavac#47 from spacewander/patch-3

增加C/C++中的makefile编辑内容

README.md

@@ -140,6 +140,9 @@
 * [CGDB中文手册](https://github.com/leeyiw/cgdb-manual-in-chinese)
 * [ZMQ 指南](https://github.com/anjuke/zguide-cn)
 * [How to Think Like a Computer Scientist](http://www.ituring.com.cn/book/1203) (中英文版)
+* [跟我一起写Makefile(PDF)](http://scc.qibebt.cas.cn/docs/linux/base/%B8%FA%CE%D2%D2%BB%C6%F0%D0%B4Makefile-%B3%C2%F0%A9.pdf)
+* [GNU make中文手册](http://www.yayu.org/book/gnu_make/)
+* [GNU make 指南](http://docs.huihoo.com/gnu/linux/gmake.html)
 
 ### CSS