Upgrades to Rails 4.1. #check_pending! is now natively supported and no ...

Upgrades to Rails 4.1. #check_pending! is now natively supported and no longer needs explicit invocation. Using secrets.yml -- to reverse this, if undesired, re-create secret_token.rb initializer (see previous revision) and remove secrets.yml. Using the new hybridized cookie serializer. Most other updates are with regard to usage, and 4.1 update docs should be reviewed, as some things have changed.