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/theseer/tokenizer/src/Tokenizer.php

@@ -0,0 +1,149 @@
+<?php declare(strict_types = 1);
+namespace TheSeer\Tokenizer;
+
+use function var_dump;
+
+class Tokenizer {
+
+    /**
+     * Token Map for "non-tokens"
+     *
+     * @var array
+     */
+    private $map = [
+        '(' => 'T_OPEN_BRACKET',
+        ')' => 'T_CLOSE_BRACKET',
+        '[' => 'T_OPEN_SQUARE',
+        ']' => 'T_CLOSE_SQUARE',
+        '{' => 'T_OPEN_CURLY',
+        '}' => 'T_CLOSE_CURLY',
+        ';' => 'T_SEMICOLON',
+        '.' => 'T_DOT',
+        ',' => 'T_COMMA',
+        '=' => 'T_EQUAL',
+        '<' => 'T_LT',
+        '>' => 'T_GT',
+        '+' => 'T_PLUS',
+        '-' => 'T_MINUS',
+        '*' => 'T_MULT',
+        '/' => 'T_DIV',
+        '?' => 'T_QUESTION_MARK',
+        '!' => 'T_EXCLAMATION_MARK',
+        ':' => 'T_COLON',
+        '"' => 'T_DOUBLE_QUOTES',
+        '@' => 'T_AT',
+        '&' => 'T_AMPERSAND',
+        '%' => 'T_PERCENT',
+        '|' => 'T_PIPE',
+        '$' => 'T_DOLLAR',
+        '^' => 'T_CARET',
+        '~' => 'T_TILDE',
+        '`' => 'T_BACKTICK'
+    ];
+
+    public function parse(string $source): TokenCollection {
+        $result = new TokenCollection();
+
+        if ($source === '') {
+            return $result;
+        }
+
+        $tokens = \token_get_all($source);
+
+        $lastToken = new Token(
+            $tokens[0][2],
+            'Placeholder',
+            ''
+        );
+
+        foreach ($tokens as $pos => $tok) {
+            if (\is_string($tok)) {
+                $token = new Token(
+                    $lastToken->getLine(),
+                    $this->map[$tok],
+                    $tok
+                );
+                $result->addToken($token);
+                $lastToken = $token;
+
+                continue;
+            }
+
+            $line   = $tok[2];
+            $values = \preg_split('/\R+/Uu', $tok[1]);
+
+            if (!$values) {
+                $result->addToken(
+                    new Token(
+                        $line,
+                        \token_name($tok[0]),
+                        '{binary data}'
+                    )
+                );
+
+                continue;
+            }
+
+            foreach ($values as $v) {
+                $token = new Token(
+                    $line,
+                    \token_name($tok[0]),
+                    $v
+                );
+                $lastToken = $token;
+                $line++;
+
+                if ($v === '') {
+                    continue;
+                }
+
+                $result->addToken($token);
+            }
+        }
+
+        return $this->fillBlanks($result, $lastToken->getLine());
+    }
+
+    private function fillBlanks(TokenCollection $tokens, int $maxLine): TokenCollection {
+        $prev = new Token(
+            0,
+            'Placeholder',
+            ''
+        );
+
+        $final = new TokenCollection();
+
+        foreach ($tokens as $token) {
+            $gap = $token->getLine() - $prev->getLine();
+
+            while ($gap > 1) {
+                $linebreak = new Token(
+                    $prev->getLine() + 1,
+                    'T_WHITESPACE',
+                    ''
+                );
+                $final->addToken($linebreak);
+                $prev = $linebreak;
+                $gap--;
+            }
+
+            $final->addToken($token);
+            $prev = $token;
+        }
+
+        $gap = $maxLine - $prev->getLine();
+
+        while ($gap > 0) {
+            $linebreak = new Token(
+                $prev->getLine() + 1,
+                'T_WHITESPACE',
+                ''
+            );
+            $final->addToken($linebreak);
+            $prev = $linebreak;
+            $gap--;
+        }
+
+        return $final;
+    }
+}