• Relay is now built with Babel 6.
• Upgraded the Babel Relay plugin to graphql-js 0.6.0. Developers interested
  in upgrading to graphql-js 0.6.0 might have to make some changes to their
  existing GraphQL schemas. Read the migration guide for more information:
  https://gist.github.com/steveluscher/ffc1dfefbb10ad280c8a4c520a5c201c
• Debug information detailing every step of a Relay mutation is now printed to
  the console when DEV is true, and console.groupCollapsed and
  console.groupEnd are available.
• The this.props.relay prop passed into components by Relay.Container now
  exposes applyUpdate and commitUpdate methods for dispatching mutations
  in the context of the current Relay.Environment.
• RANGE_DELETE mutations can now remove multiple nodes from a connection,
  because deletedIDFieldName can now point to a plural field.
• You can now define rangeBehaviors as a function that receives the connection
  arguments and returns one of GraphQLMutatorConstants.RANGE_OPERATIONS.
• RelayNetworkDebug#init now lets you pass in a RelayEnvironment against
  which you would like to debug. This does not yet allow you to debug more than
  one environment at a time, but at least you can make the choice of which one.
• RelayReadyState now contains an events array; a stream of events that can
  be accessed from a RelayReadyStateCallback. You can reduce over this list of
  events to implement any kind of custom rendering logic you like.
• this.props.variables now reflects the variables after being processed with
  prepareVariables. The fact that variables were the un-prepared values was
  a source of confusion for many.
• Fixed a bug where prepareVariables could be called twice, breaking
  components with non-idempotent prepareVariables functions.
• Relay now warns when you try to set a variable using setVariables, or
  produce one through prepareVariables, that you have not declared in
  initialVariables upfront.
• It's now possible for the stale prop of a readyState to change even if
  there was previously an error present.
• Fixed a bug formatting error messages when the error being pointed to starts
  at column 0.
• A container definition can now optionally include a
  shouldComponentUpdate: () => boolean function. If specified, this function
  always overrides the default implementation (ie. there is no fall-through to
  the default).