PHP can no longer be built without Reflection and SPL
Don't use Yaml 2.2

Currently it's only in beta but pyrum marked it as stable and that solved installation issues for now and when it's released.
Update Changelog
Also make sure we don't use yaml 2.2 with composer for 3.7
Prepare release
Upgrade DbUnit
Prepare release
Fixes sebastianbergmann/phpunit-mock-objects#81.

 * Ensure that mock methods preserve pass-by-reference.
Merge pull request #776 from whatthejeff/phpunit-mock-objects/issue_81
Earlier declaration of $time in Util/PHP.php.

When running tests in strict mode, PHP complains about an undeclared $time variable at the end of the processChildResult function. Moving the $time initialisation at the top of the function fixes it.
Merge pull request #778 from noihex/3.7