chore(release): version 3.1.2 [skip ci]

<a name="3.1.2"></a>
## [3.1.2](v3.1.1...v3.1.2) (2018-02-09)

### Bug Fixes

* add title and badges to Readme ([f31c7f6](f31c7f6))

package.json

@@ -1,6 +1,6 @@
 {
  "name": "aws-serverless-express",
- "version": "3.1.1",
+ "version": "3.1.2",
  "description": "This library enables you to utilize AWS Lambda and Amazon API Gateway to respond to web and API requests using your existing Node.js application framework.",
  "keywords": [
  "aws",