Add docker-credential-ecr-login binary

Signed-off-by: Arthur Diniz <arthurbdiniz@gmail.com>

Dockerfile

@@ -1,3 +1,9 @@
+FROM golang:1.9 AS build-ecr-plugin
+
+RUN go get -u github.com/awslabs/amazon-ecr-credential-helper/ecr-login/cli/docker-credential-ecr-login
+WORKDIR /go/src/github.com/awslabs/amazon-ecr-credential-helper
+RUN make linux-amd64
+
 FROM docker
 
 RUN apk --no-cache update && \
@@ -22,4 +28,6 @@ RUN apk --no-cache update && \
       update-ca-certificates && \
       rm -rf /var/tmp/ && \
       rm -rf /tmp/* && \
-      rm -rf /var/cache/apk/*
+      rm -rf /var/cache/apk/*
+
+COPY --from=build-ecr-plugin /go/src/github.com/awslabs/amazon-ecr-credential-helper/bin/linux-amd64/docker-credential-ecr-login /bin