Update docker test scripts to support Node.js 6 and 10 buildings

run_tests_docker.sh

@@ -1,9 +1,34 @@
+#!/bin/bash
+
+usage() {
+    /etc/init.d/postgresql stop
+    echo "Usage: $0 [nodejs10|nodejs6]"
+    exit 1
+}
+
+echo "$0 $1"
+
 # start PostgreSQL
 /etc/init.d/postgresql start
 
+echo "Node.js version:"
+node -v
+
 # install dependencies
-npm install -g yarn@0.27.5
-yarn
+NODEJS_VERSION=${1-nodejs10}
+
+if [ "$NODEJS_VERSION" = "nodejs10" ];
+then
+    echo "Node.js version:"
+    npm -v
+    npm install
+elif [ "$NODEJS_VERSION" = "nodejs6" ];
+then
+    npm install -g yarn@0.27.5
+    yarn
+else
+    usage
+fi
 
 # run tests
 npm test