[#71377102] delete date in some item fields

Squashed commit of the following:

commit 6951f8643392a0df33625fb0059b2e32c35f9966
Merge: d015b46 13fba8b
Author: Matus Kmit <matus.kmit@zhdk.ch>
Date:   Tue May 27 13:00:35 2014 +0200

    Merge branch 'next' into mk_item_date_fields

    Conflicts:
    	features/step_definitions/examples/inventarhelfer_steps.rb
    	features/step_definitions/languages/de_steps.rb

commit d015b46f112bd60bf28e900bb4da91eff60dda0d
Author: Matus Kmit <matus.kmit@zhdk.ch>
Date:   Tue May 27 10:42:30 2014 +0200

    [FIX CI] features/examples/inventarhelfer.feature

commit 22b43b7ea6e797cbbc1a780499ee15360589ca4f
Author: Matus Kmit <matus.kmit@zhdk.ch>
Date:   Tue May 27 10:42:00 2014 +0200

    updated selenium-webdriver

commit 46a33629d6f8283c6a66b12f2a636dcfd675d63e
Author: Matus Kmit <matus.kmit@zhdk.ch>
Date:   Mon May 26 15:54:17 2014 +0200

    updated cucumber subset

commit 11754065f6eb8a140cc8cced538f4e10c193dd0a
Author: Matus Kmit <matus.kmit@zhdk.ch>
Date:   Mon May 26 15:26:28 2014 +0200

    impl

commit 2c6b707cffae74d65dbd6d4ca907031720b92d81
Author: Matus Kmit <matus.kmit@zhdk.ch>
Date:   Mon May 26 15:01:22 2014 +0200

    test