### Highlights

 - __A new construct library for AWS Step Functions__
   ([docs](https://github.com/awslabs/aws-cdk/blob/master/packages/%40aws-cdk/aws-stepfunctions/README.md)).
   The library provides rich APIs for modeling state machines by exposing a
   programmatic interface for [Amazon State
   Language](https://docs.aws.amazon.com/step-functions/latest/dg/concepts-amazon-states-language.html).
 - __A new construct library for Amazon S3 bucket deployments__
   ([docs](https://github.com/awslabs/aws-cdk/blob/master/packages/%40aws-cdk/aws-s3-deployment/README.md)).
   You can use now automatically populate an S3 Bucket from a .zip file or a
   local directory. This is a building block for end-to-end support for static
   websites in the AWS CDK.

### Bug Fixes

* **aws-apigateway:** make LambdaRestApi proxy by default ([#963](#963)) ([a5f5e2c](a5f5e2c)), closes [#959](#959)
* **aws-cdk:** Allow use of assumed roles behind a proxy ([#898](#898)) ([f2b1048](f2b1048))
* **aws-cdk:** Auto-delete stacks that failed creating before new attempt ([#917](#917)) ([2af8309](2af8309))
* **aws-cloudfront:** expose distributionId ([#938](#938)) ([f58d98c](f58d98c))
* **aws-dynamodb:** don't emit empty array properties ([#909](#909)) ([841975a](841975a))
* **docs:** use ..code to display file structure in "writing constructs" ([#935](#935)) ([b743362](b743362))

### Features

* **assets:** isZipArchive indicates if this is a zip asset ([#944](#944)) ([65190f9](65190f9))
* **aws-cdk:** deploy supports CloudFormation Role ([#940](#940)) ([393be6f](393be6f)), closes [#735](#735)
* **aws-cloudformation:** allow specifying custom resource type ([#943](#943)) ([9de3a84](9de3a84))
* **aws-cloudformation:** correctly handle the templateConfiguration property in the CreateUpdateStack Pipeline Action. ([#923](#923)) ([d251a46](d251a46))
* **aws-cloudfront:** add support for "webAclId" ([#969](#969)) ([3ec9d76](3ec9d76))
* **aws-codedeploy:** add auto rollback configuration to server Deployment Group. ([#925](#925)) ([7ee91cf](7ee91cf))
* **aws-codedeploy:** add instance tag filter support for server Deployment Groups. ([#824](#824)) ([e6e8c51](e6e8c51))
* **aws-codedeploy:** add support for setting CloudWatch alarms on a server Deployment Group. ([#926](#926)) ([27b26b1](27b26b1))
* add support for Step Functions ([#827](#827)) ([81b533c](81b533c))
* **aws-lambda:** add grantInvoke() method ([#962](#962)) ([1ee8135](1ee8135)), closes [#961](#961)
* **aws-lambda:** improvements to the code and runtime APIs ([#945](#945)) ([36f29b6](36f29b6)), closes [#902](#902) [#188](#188) [#947](#947) [#947](#947) [#664](#664)
* **aws-logs:** extractMetric() returns Metric object ([#939](#939)) ([5558fff](5558fff)), closes [#850](#850)
* **aws-s3:** initial support for website hosting ([#946](#946)) ([2d3661c](2d3661c))
* **aws-s3-deployment:** bucket deployments ([#971](#971)) ([84d6876](84d6876)), closes [#952](#952) [#953](#953) [#954](#954)
* **docs:** added link to CloudFormation concepts ([#934](#934)) ([666bbba](666bbba))

### BREAKING CHANGES

* **aws-apigateway:** specifying a path no longer works. If you used to
provide a '/', remove it. Otherwise, you will have to supply `proxy: false`
and construct more complex resource paths yourself.
* **aws-lambda:** The construct `lambda.InlineJavaScriptLambda` is no longer supported. Use `lambda.Code.inline` instead; `lambda.Runtime.NodeJS43Edge` runtime is removed. CloudFront docs [stipulate](https://docs.aws.amazon.com/AmazonCloudFront/latest/DeveloperGuide/lambda-requirements-limits.html#lambda-requirements-lambda-function-configuration) that you should use node6.10 or node8.10. It is always possible to use any value by instantiating a `lambda.Runtime` object.