docker: change release image build to debian, roll quay back to v6

leveldown segfaults on alpine node8 but seems find on debian.
change out alpine build for a debian build and roll quay build back
to node 6 since it doesn't support multi stage builds

Dockerfile

@@ -1,28 +1,32 @@
-# -- NODE 8
-FROM  mhart/alpine-node:8 AS base
+# -- BASE
+FROM buildpack-deps:jessie-curl AS base
 ENV storage__path /var/data/skyring
 ENV NODE_ENV=production
+RUN apt-get update && apt-get install -y \
+  build-essential curl g++ make tar python
+
+ENV NODE_VERSION 8.4.0
+
+RUN curl -SLO "https://nodejs.org/dist/v$NODE_VERSION/node-v$NODE_VERSION-linux-x64.tar.xz"
+RUN tar -xJf "node-v$NODE_VERSION-linux-x64.tar.xz" -C /usr/local --strip-components=1
 
 # -- BUILD
 FROM base AS build
 
 COPY package*.json /opt/skyring/
 WORKDIR /opt/skyring
+RUN npm install && mv node_modules prod_node_modules
 
-RUN apk update && \
-    apk upgrade && \
-    mkdir -p /var/data/skyring && \
-    apk add python make g++ git && \
-    npm install
-
-RUN mv node_modules prod_node_modules
-
-FROM base AS skyring
+# -- RELEASE
+FROM debian:jessie-slim as skyring
 RUN mkdir -p /var/data/skyring
 WORKDIR /opt/skyring
 VOLUME /etc
 VOLUME /var/data/skyring
 
+COPY --from=build /usr/local/bin/node /usr/local/bin/node
+COPY --from=build /usr/local/bin/npm /usr/local/bin/npm
+COPY --from=build /usr/local/include/node /usr/local/include
 COPY --from=build /opt/skyring/prod_node_modules ./node_modules
 COPY . .
 CMD ["node", "index.js"]

quay/Dockerfile

@@ -1,4 +1,4 @@
-FROM  mhart/alpine-node:8
+FROM  mhart/alpine-node:6
 COPY . /opt/skyring
 WORKDIR /opt/skyring
 RUN apk update && \