git-svn-id: https://rt-thread.googlecode.com/svn/trunk@2185 bbd45198-f89e-11dd-88c7-29a3b14d5316

As you know, most branches of RT-thread project has used "scons" tools to compile project or construct MDK project automatically for specific branch. this is a very simple and effective method.Now this method could have been available for sep4020, and the necessary script files has been wrote and uploaded.  

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@1293 bbd45198-f89e-11dd-88c7-29a3b14d5316