finish home page of lecture
when cannot find datetime in lecture notification, set the datetime to timezone.now()
download_date is not taken in consideration now
finish home page of activity
add date in the home page of both lecture and activity
fix typo, amend css of lecture and activity
delete link in activity message of home page
amend code style in table.js
Merge pull request #15 from doyoubi/develop

完成显示讲座信息和活动信息的表格页面