[3.0] Move relation providers in compile time

[goetas]

This moves relation providers at compile (cache) time.

continuation of #266 and #267

[goetas]

All the tests that use collections are failing as per how collections are handled, their relations are not static.

We have some options:

1. drop support for collection/vnd representations (~20% of the issues on github are related to collections) and wait for a better solution (user-land typed classes for collections)

2. drop support for collection/vnd representations as they are now and offer an alternative version for:

   • VndErrorRepresentation results can be achieved by playing a bit with expression language and not allowing the user to choose the rel name (imo still good compromise)
   • CollectionRepresentation could be more difficult, my idea is to drop what can not be achieved and standardize the pagination-mode by offering some presets but not customizable as they are now. (as it is now, is not possible to generate nelmio-api-doc for CollectionRepresentation, if we make it cacheable it will be possible)

The second proposal is similar to the first excerpt that we offer to the user some alternatives.

[goetas]

ok, this are the results so far regarding my previous comment:

• VndErrorRepresentation not works almost as before.

  • Dropped the support for additional "title" attribute as it is not part of the specs.
  • Now the constructor takes string as arguments instead of Relation.

• CollectionRepresentation does not allow customization of rel names and addition of extra relation information. Prefer to implement a proper typed "CollectionRepresentation-style" class declaring the data type present inside (this will allow also a better generation of documentation when using nelmio api-doc)

IMO all the features that are in the Hateoas\Representation namespace are too connected to the user-application logic and too opinionated for a generic use, so any change will always be a compromise.

[adrienbrault]

Looks good.

Regarding the CollectionRepresentation, we can keep it as an easy way to create collections and/or a sample