add open source OSes info

Author: chyyuu-tsinghua-cs

Diff for: opensource_os_list.md

@@ -0,0 +1,25 @@
+# open source OSes
+
+## elastos (china)
+ - site: http://elastos.org/
+ - code: https://github.com/elastos/ElastosRDK5_0 
+ - code: https://github.com/elastos/HD-Elastos
+ - code: https://github.com/elastos/ElastosOS_HomeHub
+
+## rt-thread (china)
+ - site: http://www.rt-thread.org/
+ - code: https://github.com/RT-Thread/rt-thread
+ - docs: https://github.com/RT-Thread/rtthread-manual-doc
+  
+## Sylix OS(china)
+ - site: http://www.sylixos.com/
+ - code: http://git.sylixos.com/cgit/
+ 
+## Fast OS (china)
+ - code: https://github.com/yangshanjin/fos
+ - docs: http://blog.csdn.net/oYangShanJin
+ 
+## Do Jian Yan OS (china)
+ - site: http://www.djyos.com/
+ - code: http://www.djyos.com/download/djysdkV1.1.1-20150420.rar
+ - docs: http://www.djyos.com/?page_id=50