Basics of landing page markup complete.

No actions. No selection. Nothing happens when you hit the button a hundred times. But Card #17 is toast.

RSpec status:	 		17 example, 0 failures, 1 pending
Teaspoon status:	 	117 tests: 0 pass, 0 fail, 0 errs, 0 todo, 0 omitted
Custom RuboCop rules:	None
Inline RuboCop disabling:	None (in non-generated code)

Trello cards authorising work:
* https://trello.com/c/id6ll2WZ/17-basic-landing-page-structure-in-specs-and-code