Check whether tile has already been cloned. If true, display warning
Provide a link to the environment if it has already been cloned
Use innerHTML instead of appendChild(document.createTextNode())
Prevent env from being re-cloned if user presses Back on env page; redirect to new-env instead.
Open already cloned link in new tab
Clicking marker on homepage map opens env in new tab
Merge pull request #53 from Precise-Pixels/env-map-prevent-duplicate-clones

[READY] Prevent duplicate environment clones