Rev golang builders to docker 17.05. (#56)

* Rev golang builders to Docker 17.05.
* Leave bazel at 1.12.6 until issues are resolved.

bazel/Dockerfile

@@ -5,7 +5,7 @@ RUN \
     apt-get update && \
     apt-get -y install python software-properties-common && \
 
-    # Install Docker 1.12.6 (https://docs.docker.com/engine/installation/linux/ubuntu/)
+    # Install Docker (https://docs.docker.com/engine/installation/linux/ubuntu/)
     apt-get -y install curl \
         apt-transport-https \
         ca-certificates && \
@@ -17,7 +17,6 @@ RUN \
        main" && \
     apt-get update && \
     apt-get -y install docker-engine=1.12.6-0~ubuntu-trusty && \
-
     add-apt-repository ppa:webupd8team/java && \
     apt-get update && \
 

golang-project/Dockerfile.alpine

@@ -2,9 +2,9 @@ FROM gcr.io/cloud-builders/go:alpine
 
 # Docker installation instructions from:
 # http://wiki.alpinelinux.org/wiki/Docker#Installation
-RUN echo "http://nl.alpinelinux.org/alpine/v3.5/community" >> /etc/apk/repositories && \
+RUN echo "http://nl.alpinelinux.org/alpine/v3.6/community" >> /etc/apk/repositories && \
     apk update && \
-    apk add docker=1.12.6-r0
+    apk add docker=17.05.0-r0
 
 COPY gopath/bin/golang_project /builder/
 COPY golang_project.ash /builder/bin/

golang-project/Dockerfile.wheezy

@@ -2,39 +2,26 @@ FROM gcr.io/cloud-builders/go:wheezy
 
 ENV DOCKER_SHA256 cadc6025c841e034506703a06cf54204e51d0cadfae4bae62628ac648d82efdd
 
-RUN apt-get -qqy update && \
-    apt-get install -qqy curl && \
-
-    # Install Docker from pre-built binaries.
-    curl -fSL "https://get.docker.com/builds/Linux/x86_64/docker-1.12.6.tgz" -o docker.tgz && \
-    echo "${DOCKER_SHA256} *docker.tgz" | sha256sum -c - && \
-    tar -xzvf docker.tgz && \
-    chmod +x docker/* && \
-    mv docker/* /usr/bin && \
-    rmdir docker/ && \
-    rm docker.tgz
-
-# TODO(jasonhall): Install Docker 1.12.6 using apt-get.
-# This seems to be blocked on
-# https://github.com/docker/docker/issues/30547
-#RUN \
-#    # This makes add-apt-repository available.
-#    apt-get update && \
-#    apt-get -y install software-properties-common && \
-#
-#    # Install Docker 1.12.6 (https://docs.docker.com/engine/installation/linux/debian/)
-#    apt-get -y install apt-transport-https \
-#        ca-certificates \
-#        python-software-properties && \
-#    curl -fsSL https://yum.dockerproject.org/gpg | apt-key add - && \
-#    apt-key fingerprint 58118E89F3A912897C070ADBF76221572C52609D && \
-#    add-apt-repository \
-#        "deb https://apt.dockerproject.org/repo/ \
-#        debian-$(lsb_release -cs) \
-#        main" && \
-#    apt-get update && \
-#    apt-get -y install docker-engine=1.12.6-0~stretch && \
-#    docker run hello-world
+# Install Docker per https://docs.docker.com/engine/installation/linux/debian/
+RUN \
+    # This makes add-apt-repository available.
+    apt-get -qqy update && \
+    apt-get -y install software-properties-common \
+        apt-transport-https \
+        ca-certificates \
+        python-software-properties && \
+	curl -fsSL https://download.docker.com/linux/debian/gpg | apt-key add - && \
+	apt-key fingerprint 0EBFCD88 && \
+	# wheezy-backports is required for init-system-helpers which is required by Docker.
+	add-apt-repository "deb http://ftp.de.debian.org/debian wheezy-backports main" && \
+    add-apt-repository \
+	    "deb [arch=amd64] https://download.docker.com/linux/debian \
+	    $(lsb_release -cs) \
+	    edge" && \
+	grep -v deb-src /etc/apt/sources.list > /tmp/sources.list && \
+	mv /tmp/sources.list /etc/apt/sources.list && \
+    apt-get -qqy update && \
+    apt-get -y install docker-ce=17.05.0~ce-0~debian-wheezy
 
 COPY gopath/bin/golang_project /builder/golang_project
 COPY golang_project.bash /builder/bin/