Change display order of categories & addons

This code won't work without some DB changes, which I'll commit soon.
Fix some display issues in the admin addon list
Fix some display issues in the admin category list
Can now change display order of customer fields

Needs some DB updates to function.
Small oops from previous commit
Bug in default "Order By" in model.class
Predefined values on new customer form

Text, Country and State will now respect the predefined value field
everywhere.
Changed admin page country/state fields from ajax

Still uses some ajax, but also generates it in php for the initial page
load.
Fixed "Sales by year" chart from dashboard

Year was hardcoded as 2005 in places
DB changes for the recent display order features