EZP-23090: Fix Solr 4.7 deprecated warnings

This pull request fixes warnings on deprecated classes and introduces the Solr 4.7+ proper way of dealing with (language specific) collation fields.

As a side effect, a potential annoyance was discovered with XInclude as introduced with eZ Find 5.3.0: only a single xml element can be included in this way. In order to allow the inclusion of lists of field and field-type definitions, the include strategy was changed to the use of SGML entities. This is also reflected in the language specific field type definitions which now hosts two definitions, one for general text analysis and a second one for the Collation fields used for sorting object names.