added role preview for preview view in backend and preview param in frontend for presentations
fix Kwf_Form_Field_ImageViewer

was completely broken.
TODO: don't use fixed preview size
ShowSelect implemented

shows the value from a Field_Select
fix toStringField

that is the right way to do that
prevent error if field is not set
Merge remote branch 'github/3.3' into 3.3
template is optional
bugfix device image name changed
add version to generated setup.php

fixes issues when incompatible changes are made to generated setup.php
(especially when changing branches in kwf)
Merge branch '3.1' into 3.2
Merge branch '3.2' into 3.3
increase cache setup version because of Kwf_Util_SessionHandler