Bump Rails version to 4.1.7

* http://www.schneems.com/2014/11/07/i-ram-what-i-ram.html
Split out violations into separate table

  * Makes `Violation` inherit from `ActiveRecord::Base` and adds associated
    table
  * Adds `has_many :violations` association to `Build`
  * Updates creation of `violations` in `style_guide`'s
  * Adds `violation` factory

https://trello.com/c/OLdRI0mO/336-split-out-violations-into-separate-table
Remove serialization of violations_archive on Build

Follow up to https://github.com/thoughtbot/hound/pull/493. We have no need to
serialize this data.
Rescue requests that set status

Setting a pull request status requires at least "push" permissions. When we
create "Services" team for Hound we only set "pull" permissions, which is not
enough to create statuses.

Note: that this affects about half the organizations, since we will add Hound to
an existing team, if it meets certian requirements.
Rescue all status change requests
Add Stripe Webhooks for Subscription Cancellation

* Disable repo if payments begin to fail due to expired card etc.
* Allows for future webhook integration

* Pulled the fixture (using `load_template`) from:
  * https://github.com/buttercloud/stripe_tester/blob/master/stripe_webhooks/2014-10-07/customer_subscription_deleted.yml

* Stripe webhook cheat sheet: https://www.petekeen.net/stripe-webhook-event-cheatsheet

https://trello.com/c/WulP3aqK

Laila changes
Drop delayed_jobs table since we are using resque
Bump rails version to 4.1.8

* Using secrets.yml which added in 4.1
* Using assets.rb inside initializers
Load staging.rb from production.rb
Add `UNICORN_TIMEOUT` to configure app timeout
Bump Rails version to 4.2
Review CoffeScript *.coffee.js files

https://trello.com/c/QdQKEB6e
Merge branch 'master' of github.com:thoughtbot/hound