User Story 62, Admin User Index Page

[iandouglas]

As an admin user
When I click on the "Users" link in the nav
Then my current URI route is "/admin/users"
And I see all users in the system who are not merchants nor admins
Each user's name is a link to a show page for that user ("/admin/users/5")
Next to each user's name is the date they registered
I see a "disable" button next to any users who are not yet disabled
I see an "enable" button next to any users whose accounts are disabled

Checklist:

• base code tests are written
• base code is written to pass tests
• edge case ("sad path") tests written (if required)
• edge case code written (if required)
• code is reviewed
• branch is merged
• all tests still pass

child of #4

depends on #71