Change user logout in frontend from ?logout to fixed url /kwf/user/logout
Delete autologin-cookie in clearIdentity
Execute autologin in Kwf_Setup
Remove User_BoxAbstract which is not needed anymore
Add Plugin_LoginAbstract which ist extended by Password- and Login-Plugin
Only add ?{QUERY_STRING} when it is not empty

Avoids the form to be sent to e.g. 'login?'
Revert "Delete autologin-cookie in clearIdentity"

This reverts commit 44e729676e0d2fcfd017b898e92373db164d0ec1.
Add Kwf_Setup::hasAuthedUser to check user without creating user model
Set autologin-cookie always for whole domain
Improve Autologin
Remove last direct call of Zend_Session::sessionExists
Kwf_Setup::hasAuthedUser() checks user model

Only checking whether there is something stored in Kwf_Auth is too insecure
Add commment
Set Zend_Session:: = true for unit tests

Otherwise the Zend_Session::writeClose() call in Kwf_Media would stop following session activities
Kwf_Setup::hasAuthedUser also checks for storage to improve performance
Merge pull request #48 from fraxachun/master-userlogin

Master userlogin