Make the crawler work

1) add the crawler binary and fix the crawler library
2) remove the readiness probe in the search backend
3) add config for redis keystore
4) add github_api_secret.txt file with instructions

api/internal/crawl/cmd/crawler/Dockerfile

@@ -0,0 +1,15 @@
+FROM golang:1.11 AS build
+
+ARG GO111MODULE=on
+
+WORKDIR /go/src/sigs.k8s.io/kustomize/api/internal/crawl
+COPY . /go/src/sigs.k8s.io/kustomize//api/internal/crawl
+
+RUN go mod download
+RUN CGO_ENABLED=0 go install -v ./cmd/crawler/crawler.go
+
+FROM scratch
+COPY --from=build /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/
+COPY --from=build /go/bin/crawler /
+ENTRYPOINT ["/crawler"]
+CMD []