[#84195546] fixing package delete (retire if associated to some contracts)

Squashed commit of the following:

commit da64ad9912d7711f518a51cbf7c495ac8621a549
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Fri Dec 19 09:52:40 2014 +0100

    [FIX CI]

commit d2fc7628a6b788ea88effb654788d7f8c706916b
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Fri Dec 19 00:20:26 2014 +0100

    regenerated dumps

commit b11bd887a3719f88b7ac2c922c9daf0b960cf801
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Thu Dec 18 23:55:56 2014 +0100

    regenerated dumps

commit edb0a3852ace02c75a6412eafeca3e57b1f53530
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Thu Dec 18 23:38:03 2014 +0100

    package scenarios

commit b0b47ce3b300704749a790a66aacd9f5aae27b07
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Thu Dec 18 01:24:08 2014 +0100

    regenerated dumps

commit 86667abdf6bbda5bcb92e65bec47cff4b1bcb62f
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Wed Dec 17 14:09:18 2014 +0100

    regenerated dumps

commit 0b15336f1cd193b09c2037b16206c4dd62c44a41
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Wed Dec 17 12:21:15 2014 +0100

    [FIX CI]

commit 43072abbe7b8810cf8d7747cf34a9d555c7c5b26
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Wed Dec 17 10:49:50 2014 +0100

    [FIX CI] removing redundant save that was firing callbacks twice

commit f947591e1a9bedbb84766213532ff674597eb40b
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Wed Dec 17 01:13:35 2014 +0100

    fixing override

commit c6ff90f892132144f874dd6050df21e0be61ce92
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Wed Dec 17 00:50:33 2014 +0100

    item_packages related to contracts are retired instead to be destroyed (because foreign keys)