Adds DataCollectionOptions class which works as a container for all data collection specific options. It works similar to the already established Options class, but since options are already big enough I decided to move this into it's own class.

Init happens normally using nested arrays:

\Sentry\init([
    'data_collection' => [
        'http_headers' => [
            'request' => [
                'mode' => 'allowList'
            ]
        ]    
    ]
]);

Also implements ArrayAccess to make accessing nested fields more intuitive and to avoid constructs such as:

$options->getDataCollection()->getHttpHeaders()['request']['terms']

and we can instead use

$options->getDataCollection()['http_headers']['request']['terms']