Update Docker image
Update Docker image

- Go 1.8.1
- Amazon Linux 2017.03

CAT: #chore

eawsy/aws-lambda-go-shim,eawsy/aws-lambda-go-shim,eawsy/aws-lambda-go-shim,eawsy/aws-lambda-go-shim,eawsy/aws-lambda-go-shim,eawsy/aws-lambda-go-shim,eawsy/aws-lambda-go-shim