Removed autoload of bootstrap.php

Removed bootstrap.php from composer files section to disable it's auto-include. Was breaking bitrix during development.

Fix phpunit.xml.dist

Fixed path to bootstrap.php in phpunit.xml.dist.

Phpunit version update

Added support for newer phpunit versions.
Changed package name in composer.json
Updated package description and usage information.

New package name is dcodeteam/phpunit-for-bitrix