Big gems and Gemfile cleanup

Squashed commit of the following:

commit 85af059913866ce1670969cb88ddb1eb8b148580
Author: Thomas Schank <DrTom@schank.ch>
Date:   Fri Oct 4 11:43:59 2013 +0200

    Refactored Gemfile

commit c0b5fef44d79a0ab06c9e831b8f45a196e5ee784
Author: Thomas Schank <DrTom@schank.ch>
Date:   Fri Oct 4 11:26:49 2013 +0200

    Fix feature: confirm when not using poltergeist

commit 82e992cc97109b2f4b18bb0f0615c2083fd2e2b9
Author: Thomas Schank <DrTom@schank.ch>
Date:   Wed Oct 2 13:37:10 2013 +0200

    Reenabled animation gem

commit fcfea3de27a4d30709b5e7e5de134eb0b3caedf1
Author: Thomas Schank <DrTom@schank.ch>
Date:   Wed Oct 2 13:34:46 2013 +0200

    Removed some output configuration from cucumber

commit f3f3abc962883589c60dc165a251aca26d374105
Author: Thomas Schank <DrTom@schank.ch>
Date:   Wed Oct 2 13:08:44 2013 +0200

    Cleaned spork and other dependencies from rspec

commit 5ce09e12a1a21af7bbad39ef6d891c698a1eca7a
Author: Thomas Schank <DrTom@schank.ch>
Date:   Wed Oct 2 13:01:43 2013 +0200

    Removed some stuff from meta_key_definition; lifts requirement on rgl

commit 158ddce0fe81f64e5a18514fb358cec46d95e1dd
Author: Thomas Schank <DrTom@schank.ch>
Date:   Wed Oct 2 13:01:06 2013 +0200

    Reenabled nested set (for Copyright)

commit f22128a08b326754ab216e36202b78e68f19b3ec
Author: Thomas Schank <DrTom@schank.ch>
Date:   Wed Oct 2 12:32:33 2013 +0200

    Cleaned gems