[#75875856] [#75805622] optimizing picking list

Squashed commit of the following:

commit f73ce262ac035a27195272b8c5ea0cf40edd9a85
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Tue Aug 5 16:51:41 2014 +0200

    [FIX CI]

commit 2ce071989b187cb3e51ada4299b1d2dd151510a0
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Tue Aug 5 16:12:57 2014 +0200

    [FIX CI]

commit ced68fa4c852d17f774d7add7c4cb3e33a4e2ae6
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Tue Aug 5 11:54:20 2014 +0200

    [FIX CI]

commit 1e842f9323a322c1105369e7bf235b81c9517d07
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Tue Aug 5 10:43:20 2014 +0200

    ItemLine validation, Model#find_by_name, fixing contract_line factory

commit 199277e3293ce4d0e310de4019f02f1abf2ba5c8
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Mon Aug 4 18:30:40 2014 +0200

    tagging failing scenarios on CI, not reproducible locally

commit 6e9d422a845b3bb8477858a455f828beb1868820
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Mon Aug 4 17:10:01 2014 +0200

    [FIX CI]

commit 3a2e777af302a131d0e1c988d6a95e02a90caa75
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Mon Aug 4 16:59:24 2014 +0200

    [FIX CI]

commit e0e9a3569e86ac53f85234903ff4682a9e942fcd
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Mon Aug 4 14:56:46 2014 +0200

    @current_inventory_pool instead of @ip

commit e7ea0acfc20860d8037d50a58b245dc81cbf5901
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Mon Aug 4 12:49:18 2014 +0200

    removing @firefox tag where not needed

commit 66933e5db394b8a4cfd799dc2c91cc80e89677ff
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Mon Aug 4 12:16:03 2014 +0200

    assertion syntax (expect instead of should)

commit e63396ca4534eebf422948857afa2636bd827117
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Mon Aug 4 12:04:25 2014 +0200

    (wip) @current_inventory_pool instead of @ip

commit e9ac26af7283803785ca4d8241574e647460c24f
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Mon Aug 4 11:36:24 2014 +0200

    describe spec with type request and use plain string path

commit 1204b7c1434a2e18daf1e6753907c19864cab6d7
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Mon Aug 4 11:10:02 2014 +0200

    picking list optimization

commit 4fe7d850059a3d0fd0e12b84ada55286fc8dfa18
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Thu Jul 31 16:40:03 2014 +0200

    removing unused gems (just a try)

commit 0e78cb7e3420744966f4d1f93065c7e9b1fc2081
Author: Franco Sellitto <franco.sellitto@zhdk.ch>
Date:   Thu Jul 31 16:04:25 2014 +0200

    (wip) picking list optimization