FIX:pub_date will add 8 hours every time save article
ADD:login decorative method
add robots.txt
article title length adjust
add baidu script
hide baidu img
post tips need no login
added save button

1.added save button
2.if title is blank , give a error msg
3.give reminder if submit/save success
FIX BUG:first save and then submit trigger a bug

new article page does not have KEY value;
after first save, should ruturn and set the KEY
otherwise another aritcle will be saved. since KEY=='', it will think
it's a new article.