Revert "Add link to version 1. [ci skip]"

This reverts commit a70c705ed2cb3e98a734bff4e8260945a97d9ad4.

Revert "Update README [ci-skip]"

This reverts commit 7179fdcfa07477c96de85e61de7d8273649e388c.

Revert "Update travis for Rails 4."

This reverts commit 418887f5c92127681d6bb2ef545f016848dacb09.
Test against 4-0-stable.