Revert "Run rake rails:update"

This reverts commit d02caf6f0e3054479748887a98adbe91f45d85f6.
Revert "Install devise from github, for compatibility with rails 4.2"

This reverts commit b0372fba901719fcb85ee4bbd9d72393b3cc4725.
Revert "Update Gemfile to rails 4.2.0.beta1"

This reverts commit 969e1ccb786ebfe5c8f4ec2694eedd3ad345fea3.