Forward compatibility layer for v3.x

[goetas]

This PR adds the new cofiguration options available in 3.x (see #278) and deprecates the current settings.

This should allow a smooth transition to 3.x

[greg0ire]

Please check the SA Travis job, it's failing.

[goetas]

Silenced the static analysis in 0512c5e since the symfony phpdoc is just wrong

[greg0ire]

Please drop 0512c5e and fix the SA issue by changing the type hint that is here: https://github.com/doctrine/DoctrineMigrationsBundle/blob/master/DependencyInjection/DoctrineMigrationsExtension.php#L25 there is no type hint in Symfony for this: https://github.com/symfony/symfony/blob/master/src/Symfony/Component/DependencyInjection/Extension/ExtensionInterface.php

[goetas]

Please drop 0512c5e and fix the SA issue by changing the type hint that is here: https://github.com/doctrine/DoctrineMigrationsBundle/blob/master/DependencyInjection/DoctrineMigrationsExtension.php#L25 there is no type hint in Symfony for this: https://github.com/symfony/symfony/blob/master/src/Symfony/Component/DependencyInjection/Extension/ExtensionInterface.php

Like this 54598cd ?

[greg0ire]

using both phpstyle and phpstan style typehints to make both phpstan and phpcs happy

Weird that we have a rule that prevents that, maybe this should be reported to the coding standard repository? Anyway, if there is no phpstan exception, great!