Finished the drop downs and textbox for doing one rental + NEW SCRIPT

- New SQL Script (R5), adds default durations to the rentals.

TO DO:
- New Customer submit needs to enter into db but still load page with
current information (rental info entered in up to that point) + STORE
new customer ID to proceed to rental.
- Existing customer: Textbox needs to serve as a omnibox, once entered
needs to search all customer dbs to find matches with keyward, then
return results. Employee needs to be able to select from all returned
users and then STORE CUST ID for rental.