docker: add default Dockerfile

Dockerfile

@@ -0,0 +1,35 @@
+FROM golang:1.13-alpine as builder
+
+# Force Go to use the cgo based DNS resolver. This is required to ensure DNS
+# queries required to connect to linked containers succeed.
+ENV GODEBUG netdns=cgo
+
+ADD . /go/src/github.com/lightninglabs/governator
+
+# Install dependencies and build the binaries.
+RUN apk add --no-cache --update alpine-sdk \
+    git \
+    make \
+    gcc \
+&&  cd /go/src/github.com/lightninglabs/governator \
+&&  make \
+&&  make install
+
+# Start a new, final image.
+FROM alpine as final
+
+# Add bash and ca-certs, for quality of life and SSL-related reasons.
+RUN apk --no-cache add \
+    bash \
+    ca-certificates
+
+# Copy the binaries from the builder image.
+COPY --from=builder /go/bin/governator /bin/
+COPY --from=builder /go/bin/gvncli /bin/
+
+# Expose governator ports (rpc).
+EXPOSE 8465
+
+# Specify the start command and entrypoint as the governator daemon.
+ENTRYPOINT ["governator"]
+