Set up SMTP in production

Previously, the production environment was not set up to send emails
using the SendGrid, which was causing exceptions to be raised.
Configured the production environment and added sample environment
variables.

https://trello.com/c/QctY0Fdu
Add orders index
Restrict access to order screens
Refactoring some things
Add Stripe integration
Remove Stripe exception handling

Previously, an exception was being caught when the Stripe API returned
an error, which has not been scoped into the project yet. The exception
block has been removed from the Order controller's create action.
Add an integration test for orders

Previously, there were no integrations surrounding the Orders page,
which was making it difficult to confidently execute any future
development work. A Cucumber scenario has been added around the page.
Simplify the orders page

Previously, a lot of superfluous information was being displayed on the
orders page, which was cluttering the page and not providing much value.
The page has been refactored to include the bare summary of each order.
Add Stripe keys to test environment
Use the Travis config from suspenders
Remove test variables
Fix typo in Travis config