Mongo as separate packages? about lexikformfilterbundle

[spike31]

@snebes I have revert your PR #308 , my bad..

Because you have add a requirement on doctrine odm bundle.

You cannot force someone to have the php mongodb extension to use this bundle.
Did you understand the problem?

Maybe you need to re-open a PR from your old branch for fix the deps.

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For your propose it's not a problem about php mongo-ext, because the only deps with that lib is doctrine odm bundle who have a requirement with doctrine odm.

Lexik bundle just use doctrine odm bundle, it's just know about what to do with the bundle, not about how the bundle works in internal.

[snebes]

I understand - it would impose installing that when not in use. I've added a new PR #311 where that is moved back into require-dev.

I would also recommend merging #304 as it is another Symfony deprecation.