Auto scroll to bottom while new message,Line break if Messgae is too long
Adding a panel for Posts, A Nav bar
Prevent XSS attack, generate hyperLink and player while message contain url/youtubeUrl
Modify post panel's layout
Function:Inserting posts into DB by Ajax
Function:Insert Post into panel
Modify Post's HTML format
Modify column 'status' default value in table member
Merge branch 'chatroom' into develop

Conflicts:
	datasave.sql
Add the origin file back...