Update README.md (#2663)
Update README.md (#2663)

Add an direct API reference link (since I has got lost in the developer-guide)
aws/aws-sdk-js,aws/aws-sdk-js,GlideMe/aws-sdk-js,aws/aws-sdk-js,GlideMe/aws-sdk-js,GlideMe/aws-sdk-js,GlideMe/aws-sdk-js,aws/aws-sdk-js