(Mac trunk) bump copyright year to 2013

git-svn-id: svn://svn.transmissionbt.com/Transmission/trunk@14013 f4695dd4-2c0a-0410-b89c-da849a56a58e
update QuickLook copyright string as well.

git-svn-id: svn://svn.transmissionbt.com/Transmission/trunk@14014 f4695dd4-2c0a-0410-b89c-da849a56a58e