Cross platform git log

Squashed commit of the following:

commit 4d26cf7199cd3fc588d6a4cce484514c39a399f5
Author: Simon Walker <s.r.walker101@googlemail.com>
Date:   Mon Sep 2 18:53:57 2013 +0100

    Using correct sed expression on linux

commit 1b3c8bd3a9bff90582958820e4126ebeb3d0fb51
Author: Simon Walker <s.r.walker101@googlemail.com>
Date:   Mon Sep 2 18:50:18 2013 +0100

    Adds helper for os dependent sed

commit 4d9529469bfb52cb46dbaf0ead1fbbd758ab8baa
Author: Simon Walker <s.r.walker101@googlemail.com>
Date:   Mon Sep 2 18:42:50 2013 +0100

    Moves strip times out to separate function