add refer for arm research code

 /*
+# see: https://github.com/winlinvip/simple-rtmp-server/wiki/SrsLinuxArm
  arm-linux-gnueabi-g++ -o jmp jmp.cpp -static
  arm-linux-gnueabi-strip jmp
 */

 /*
+# see: https://github.com/winlinvip/simple-rtmp-server/wiki/SrsLinuxArm
  arm-linux-gnueabi-g++ -g -o jmp_sp jmp_sp.cpp -static
  arm-linux-gnueabi-strip jmp_sp
 */

 /*
+# see: https://github.com/winlinvip/simple-rtmp-server/wiki/SrsLinuxArm
  arm-linux-gnueabi-g++ -o test test.cpp -static
  arm-linux-gnueabi-strip test
 */