refactoring accounts edit/new views for better engine support

cleaner show/hide logic for account new/edit on type change
make purchase order number and expiration date editable

task #56887
Merge branch 'master' into edit_purchase_order_56887
missed a 1.9 hash syntax
Merge pull request #17 from tablexi/edit_purchase_order_56887

Edit purchase order number and expiration date #56887