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/hamcrest/hamcrest-php/tests/Hamcrest/AbstractMatcherTest.php

@@ -0,0 +1,68 @@
+<?php
+namespace Hamcrest;
+
+use PHPUnit\Framework\TestCase;
+
+class UnknownType {
+}
+
+abstract class AbstractMatcherTest extends TestCase
+{
+
+    const ARGUMENT_IGNORED = "ignored";
+    const ANY_NON_NULL_ARGUMENT = "notnull";
+
+    abstract protected function createMatcher();
+
+    public function assertMatches(\Hamcrest\Matcher $matcher, $arg, $message)
+    {
+        $this->assertTrue($matcher->matches($arg), $message);
+    }
+
+    public function assertDoesNotMatch(\Hamcrest\Matcher $matcher, $arg, $message)
+    {
+        $this->assertFalse($matcher->matches($arg), $message);
+    }
+
+    public function assertDescription($expected, \Hamcrest\Matcher $matcher)
+    {
+        $description = new \Hamcrest\StringDescription();
+        $description->appendDescriptionOf($matcher);
+        $this->assertEquals($expected, (string) $description, 'Expected description');
+    }
+
+    public function assertMismatchDescription($expected, \Hamcrest\Matcher $matcher, $arg)
+    {
+        $description = new \Hamcrest\StringDescription();
+        $this->assertFalse(
+            $matcher->matches($arg),
+            'Precondtion: Matcher should not match item'
+        );
+        $matcher->describeMismatch($arg, $description);
+        $this->assertEquals(
+            $expected,
+            (string) $description,
+            'Expected mismatch description'
+        );
+    }
+
+    public function testIsNullSafe()
+    {
+        //Should not generate any notices
+        $this->createMatcher()->matches(null);
+        $this->createMatcher()->describeMismatch(
+            null,
+            new \Hamcrest\NullDescription()
+        );
+    }
+
+    public function testCopesWithUnknownTypes()
+    {
+        //Should not generate any notices
+        $this->createMatcher()->matches(new UnknownType());
+        $this->createMatcher()->describeMismatch(
+            new UnknownType(),
+            new NullDescription()
+        );
+    }
+}