done:
1 sign up
2 save to db
3 check email and password
4 add salt hash
done:
upload a file
bug:
can not create a file(pemission deny)
can redirect
basic founction
version 2.0
version 2.0
merge:
1 merge login.py and login_post to login.py
2 merge regi_edit.py and regi_post.py to regi.py
3 merge avatar_show.py and avatar_post.py to avatar.py

rediret:
when rediret a url, give some message tip and wait seconds to refresh
fix some ui bussiness logic
Merge branch 'develop'
done function:
1 sign in
2 sign up
3 upload a pic
4 sign out
5 cookie and session