fix self-contained buildout. ``develop = .`` was not used and plone.app.widgets downloaded as egg, doing a source checkout instead
remove unnecessary version declarations, which let tests under 4.3 fail. updating robotframework version
Remove configuration of plone.app.event's start and end fields in the dx_bbb module. Requires plone.app.event >= 1.2, which does the widget configuration by itself. There is no point in using a previous version of plone.app.event together with plone.app.widgets.