Make Backtrace optional

[norberttech]

Resolves #201

Blacfire profiles, as expected VoidBacktrace is way faster.

• VoidBacktrace - https://blackfire.io/profiles/7fe767de-c234-4d33-addd-ba217d8c6ce4/graph
• InMemoryBacktrace - https://blackfire.io/profiles/bf6d1854-44c5-4174-a842-de226f87092f/graph

Both profiles executed against following code:

// $backtrace = new VoidBacktrace();
// $backtrace = new InMemoryBacktrace();

$matcher = (new MatcherFactory())->createMatcher($backtrace);

$value = [
    'users' => [
        [
            'id' => 1,
            'firstName' => 'Norbert',
            'lastName' => 'Orzechowicz',
            'enabled' => true,
        ],
        [
            'id' => 2,
            'firstName' => 'Michał',
            'lastName' => 'Dąbrowski',
            'enabled' => true,
        ],
    ],
    'readyToUse' => true,
    'data' => new stdClass(),
];

$pattern = [
    'users' => [
        [
            'id' => '@integer@',
            'firstName' => '@string@',
            'lastName' => 'Orzechowicz',
            'enabled' => '@boolean@',
        ],
        [
            'id' => '@integer@',
            'firstName' => '@string@',
            'lastName' => 'Dąbrowski',
            'enabled' => '@boolean@',
        ],
    ],
    'readyToUse' => true,
    'data' => '@wildcard@',
];


for ($i = 0; $i < 100; $i++) {
    $matcher->match($value, $pattern);
}