Disable the Output walkers of Entity with joins (Fixes #931)

[StudioMaX]

Fix for issue #931
There is another pull request #939 , but it will revert the functionality added by commit #828

[DonCallisto]

@hmert I've seen you merged #828. Can you take a look to this?

[Vowow]

Please merge this one

[DonCallisto]

@Vowow Waiting for maintainer of the bundle to check if everything it's ok. I can merge it too but I'm not into all bundle logic and, without test cases, I can't judge if this is good or not.
However I would expected more commitment from new maintainers .... /cc @hmert

[hmert]

@DonCallisto and @Vowow I could not figure out why we're removing walkers. But, in our project. I've tested this PR it looks OK.

[DonCallisto]

@StudioMaX can you explain this change to @hmert ?

[Vowow]

@hmert This provide a fix to a bug when you add a manyToOne column to the grid with annotation.
The error is : "The Paginator does not support Queries which only yield ScalarResults. "

[StudioMaX]

@hmert can you release a new version?