Changed name "Heptio Authenticator" to "AWS IAM Authenticator for Kubernetes"
Changed name "Heptio Authenticator" to "AWS IAM Authenticator for Kubernetes"

Signed-off-by: Nishi Davidson <f5c101d306e5248806a0da90c06d9929bb189862@amazon.com>

kubernetes-sigs/aws-iam-authenticator,kubernetes-sigs/aws-iam-authenticator,kubernetes-sigs/aws-iam-authenticator