Document (& fix) HateoasBuilder
[doc] be more verbose
[doc] typo
[doc] Fix 'The HateoasBuilder' link
[doc] typo again
cs
[doc] typo, typo, typo
[doc] Add TOC
[doc] Better TOC
cs
[doc] fix installation section
Require symfony/expression-language 2.4 stable

Because symfony 2.4 is now stable
Merge pull request #94 from lyrixx/patch-1

Require symfony/expression-language 2.4 stable
Use ~constraint for Doctrine Annotations
Update CONTRIBUTING file
cs
Remove Hateoas::getRelationsRepository()

Fixes #95
Fix setUrlGenerator() method (builder)

Closes #97
Introduce UrlGeneratorHelper

Useful to generate URLs based on configured relations

Should fix #91
Introduce ExpressionFunctionInterface

to extend the ExpressionLanguage with custom functions.

* Add 'link' function that relies on the LinkHelper class
* Add tests

Should fix #83