Squashed commit of the following:

commit 132f2647e03d39c2ef0e3bbdd885d8ffe8327d00
Author: Alex McGuire <alex.mcguire@trafigura.com>
Date:   Wed Jul 10 18:56:06 2013 +0100

    Small changes to reduce number of open file handles

commit 91dbc752e38acf7256c815e1736bafc15d7399ac
Author: Alex.McGuire <alex.mcguire@trafigura.com>
Date:   Tue Jul 9 14:02:25 2013 +0100

    Add 'pwd' command to maker

commit 15de2c2b455855f6fe107f4713dc36b080b75745
Author: Alex.McGuire <alex.mcguire@trafigura.com>
Date:   Tue Jul 9 12:10:01 2013 +0100

    Ensure old resources are deleted when an update is done