feature:2823 Add triggers for login system, load function_plugins before function_user

git-svn-id: http://piwigo.org/svn/trunk@20325 68402e56-0260-453c-a942-63ccdbb3a9ee
[trunk_admin] Update zh_CN, thanks to : dennisyan

git-svn-id: http://piwigo.org/svn/trunk@20331 68402e56-0260-453c-a942-63ccdbb3a9ee
some code comments

git-svn-id: http://piwigo.org/svn/trunk@20335 68402e56-0260-453c-a942-63ccdbb3a9ee
javascript int type instead of string

git-svn-id: http://piwigo.org/svn/trunk@20336 68402e56-0260-453c-a942-63ccdbb3a9ee