[DependencyInjection] fixed FormatterModifiersPass and "formatter_modifier.validator" service definition

And renamed formatter.class parameter to modifier_formatter.class
[Exporter] fixed FilterQueryExporter unable to resolve field when label is different then field name
fixed Resources/doc/Doctrine/orm/where_builder.rst

The documentation of Value Conversion was outdated and contained wrong information
[CacheWarmer] Cache warming is no longer optional

We must ensure the CacheWarmer is always executed in order to get the FieldSets generated.
FieldSets defined in the configuration can not be retrieved and generated during runtime.
[DependencyInjection] make "input.filter_query" service always use the factories.fieldset.label_translator configuration

As every instance is unique its possible to disable/change this when needed.