Enable ability to change default address when searching

Carl Stuart have noticed when searching for irish addresses for their customers on division level, it only returns addresses in the UK. This is because it is hardcoded to search within iso code GB, and to allow them to search outside of that you would need to go into the database and change the value of enablelookup in dba.country for all countries they want to be able to search for. They asked for a way to change the default country it searches in rather than having to enable countries and use a dropdown in system or user settings.