Add an image for git v2.16 and Chrome v63

Also adds a caching mechanism for storing the latest version in an S3 bucket.

scripts/cache-google-chrome

@@ -0,0 +1,41 @@
+#!/bin/bash
+# This script attempts to copy the latest version of the Google Chrome Debian
+# package into our own S3 bucket. Google yanks old versions regularly, making
+# it hard to keep up with all the new versions.
+
+set -e
+
+if [[ -z $AWS_ACCESS_KEY_ID || -z $AWS_SECRET_ACCESS_KEY ]]; then
+    echo "AWS credentials are not defined, skipping this step"
+    exit 0
+fi
+
+CHROME_S3_BUCKET=${1:-gitlab-google-chrome-stable}
+
+export DEBIAN_FRONTEND=noninteractive
+apt-get -y update
+apt-get -y install apt-utils curl awscli
+
+curl -sS -L https://dl.google.com/linux/linux_signing_key.pub | apt-key add -
+echo "deb [arch=amd64] http://dl.google.com/linux/chrome/deb/ stable main" > /etc/apt/sources.list.d/google.list
+
+echo "Updating apt to get Google Chrome packages..."
+
+apt-get -y -q update
+
+echo "Checking for latest Chrome version in apt repository..."
+
+LATEST_VERSION=$(apt-cache show google-chrome-stable | grep Version | sort | tail -1 | sed -e "s/Version: //")
+CHROME_DEB="google-chrome-stable_${LATEST_VERSION}_amd64.deb"
+CHROME_URL="https://s3.amazonaws.com/gitlab-google-chrome-stable/${CHROME_DEB}"
+
+echo "Checking if cache has $CHROME_DEB"
+FILE_CHECK=$(curl -sL -w "%{http_code}\\n" "$CHROME_URL" -o /dev/null)
+
+if [ "$FILE_CHECK" -eq "200" ]; then
+    echo "Latest version $LATEST_VERSION is already cached!"
+else
+    apt-get -d -y install google-chrome-stable
+    echo "Transfering $CHROME_DEB to S3 cache"
+    aws s3 cp /var/cache/apt/archives/$CHROME_DEB s3://$CHROME_S3_BUCKET
+fi