Add password and expiration for share link
[share link] add passwd & expiration: improved ui & interaction
[repo_setting] improved ui
clean up code for 'link share'; fixed bug for 'login_require_ajax'
[repo_setting] clean up code
[notice] mark related user msgs as read when close the popup
Add ENABLE_MAKE_GROUP_PUBLIC setting, default False.
Refactor group manage
Show revoke public link when group in public
[auth] Enlarge login attempt limit, and fix login attempts bug
[user-role] Select role when add a user / change role at user admin page;
            Limit guest user's operation: can not create group and library.
[notice] make msg details be clickable
added sqls for all models

During seafile server setup, it's better to import sqls than running
django "syncdb" command direclty.
[search] Refactor and remove encrypt repo checking
[email-notice] use new time format
[user role] bugfix and improvement
Use the built-in json module

Python >= 2.6 comes with json by default. simplejson is only useful for Python
<= 2.5.
Merge pull request #247 from brutasse/fix/simplejson

Use the built-in json module
[upload-link] can not get upload link when repo access permmision is read-only
[notice page] redesigned it