Allow user to add Pacakge titles from POL view

Purpose:  Rename the Linked instances accordion to "Package titles" accordion for the Package POL view. Allow users to add titles for receiving from this view so they don't need to leave the order app to finish building the order.

User story statement(s):

As an ordering librarian
I want to be able to add title information to my package POL from the orders app
so that I don't need to navigate to receiving to complete my order details.

Scenarios:

1. Scenario:
   • Given I have created an order and added a package POL
   • When is viewing the expanded "Package titles" accordion
   • Then there is an "Add" button
   • Note user must have "Edit POL" permissions to user add button
2. Scenario:
   • Given user can see "Add" button for Package titles accordion
   • When user clicks add button
   • Then select instance modal is displayed