Update the dependencies and require the SDK 3.x

[ste93cry]

As per title, along with a few dependencies (both dev and non) I updated the main SDK to version 3.x 🎉 There weren't many changes to do and the majority were in the tests. In reality, I just made the minimum amount of work to make the tests pass, taking for granted that since both unit and e2e tests are green everything is fine. If someone that is brave enough wants to try this out before merging it it would be really cool

[ste93cry]

After hours and hours of debugging, I found out the cause of the broken build: a change that happened between PHP 7.2 and 7.3 (I didn't find which one) which made sure that when an error is caught in a try statement, error_get_last() is not filled with its information. However, Xdebug maintained this behavior until 2.9.3 when the bug was fixed. Since the FrameContextifierIntegration tries to read a file path which does not exists an exception is thrown and catched, an error is also emitted and as a consequence the rest of the error handling messes up and the test fails. TLDR, Travis CI is using a bugged version of Xdebug for PHP 7.2. I have no clue about why the step with SYMFONY_VERSION=3.4.* SYMFONY_DEPRECATIONS_HELPER=disabled doesn't fail though

https://3v4l.org/Al4QW

[Jean85]

Changes look fine for me; we obviously need to fix the issues in the CI...

[ste93cry]

I updated the CHANGELOG and added support for a few new options. However, the build on PHP 7.2 keeps failing and I have no idea how to fix it once for all because even if we workaround the issue in the FrameContextifierIntegration integration it may arise somewhere else and without changing how we handle the integration of the error handler with the framework I don't see any manouver space