Build modified streamline images

The official image from streamline does not currently work for the arm64
platform. As a temporary measure, the source code and docker build scripts
have been lifted from the official images and are used to build locally.

Some additional modifications are made to reduce overall image size, these
are documented in docker/README.md

docker/streamline-src/vendor/squizlabs/php_codesniffer/tests/TestSuite7.php

@@ -0,0 +1,35 @@
+<?php
+/**
+ * A PHP_CodeSniffer specific test suite for PHPUnit.
+ *
+ * @author    Greg Sherwood <gsherwood@squiz.net>
+ * @copyright 2006-2015 Squiz Pty Ltd (ABN 77 084 670 600)
+ * @license   https://github.com/PHPCSStandards/PHP_CodeSniffer/blob/master/licence.txt BSD Licence
+ */
+
+namespace PHP_CodeSniffer\Tests;
+
+use PHPUnit\Framework\TestSuite as PHPUnit_TestSuite;
+use PHPUnit\Framework\TestResult;
+
+class TestSuite extends PHPUnit_TestSuite
+{
+
+
+    /**
+     * Runs the tests and collects their result in a TestResult.
+     *
+     * @param \PHPUnit\Framework\TestResult $result A test result.
+     *
+     * @return \PHPUnit\Framework\TestResult
+     */
+    public function run(TestResult $result=null): TestResult
+    {
+        $result = parent::run($result);
+        printPHPCodeSnifferTestOutput();
+        return $result;
+
+    }//end run()
+
+
+}//end class