Revert "submit one file."

This reverts commit b1f761390eeba052c16dd469c956acf31175a385.
Revert "Revert "submit one file.""

This reverts commit 504424127e58408bdc7d1f1cd1d6d38ae2728d12.
submit HelloWorld.java
update HelloWorld
commit a file that the name is remark.txt.
update readme.txt
Merge pull request #1 from tidecc5/master

update