Add Dockerfile.

Dockerfile

+FROM golang:1.11.6 as builder
+RUN /usr/sbin/adduser --system --no-create-home http-faccess
+RUN go get -d -v github.com/slimhazard/gogitversion && \
+    cd /go/src/github.com/slimhazard/gogitversion && \
+    make install
+
+WORKDIR $GOPATH/src/code.uplex.de/uplex-varnish/http-faccess
+COPY go.mod .
+COPY go.sum .
+
+ENV GO111MODULE=on
+RUN go mod download
+
+COPY main.go .
+COPY ./.git/ .
+RUN go generate && \
+    GOOS=linux GOARCH=amd64 go build -tags netgo -ldflags='-w -s' \
+    -o /go/bin/http-faccess
+
+FROM scratch
+COPY --from=builder /usr/share/zoneinfo /usr/share/zoneinfo
+COPY --from=builder /etc/passwd /etc/passwd
+COPY --from=builder /go/bin/http-faccess /go/bin/http-faccess
+USER http-faccess
+ENTRYPOINT ["/go/bin/http-faccess"]