some javadoc improve
test refactor
fix incorrect pre-check VoteOfMeMessage/VoteTopic logic
update TODO
fix a copy/paste error
add some common interface to refactor Servlet code
makes QueryMessageServlet Reader/Writer based
fix LogoutServlet action
fix logout use wrong session key
add HttpSession param to AbstractServlet callback
refactor DeleteMessageServlet to common interface
fix incorrect comment, JudageMessage needs logined user
JudgeMessageServlet refactor to common interface, filter out already judged request
refactor LogoutServlet to common interface
refactor PollServlet to common interface
catch JsonParseException in common place
QueryUserServlet refactor to common interface
LoginServlet refactor to common interface
use assert ...
speed up testcase