Check Out As Proxy v1

Purpose: Roughing in check out as a proxy feature. Will come back and refine the UI once we have wireframes completed.

As a patron who has authorized a proxy to borrow on their behalf
I want that proxy to be able to check books out for me
So that I don't have to do it myself

Scenarios:

1. Scenario
   • Given User A is a proxy for one or more users
   • When User A is "scanned" in Check out
   • Then a Proxy button should display
2. Scenario
   • Given the proxy button for User A
   • When clicked
   • Then I should be able to select from User A's sponsors (do this however is easiest (modal or other) - we will come back later and refine the UI once we have mock-ups)
3. Scenario
   • Given Sponsor X on User A's sponsor list
   • When selected
   • Then sponsor X's details should display along with User A's details on Check out (or you can just replace User A's details with Sponsor X's for now - we are just roughing in the functionality and will come back with screen mock-up later)
4. Scenario
   • Given Sponsor X has been selected as User A's sponsor
   • When an item is checked out
   • Then:
     • The loan should be counted in Sponsor X's Loan statistics on the user profile page
     • The loan should display on Sponsor X's Loans page
     • The Loan Details page for the loan should display:
       • Borrower = Sponsor X
       • Proxy borrower = User A