Fixed: CS, exception message typo, removed unused import
EZP-20848: enable Field converter throwing an exception when field is not searchable
EZP-20848: add excpetion on invalid criterion
EZP-20848: tested using Field criterion on non searchable field
EZP-29848: throw NotImplementedException if legacy storage does not support search on otherwise searchable field
EZP-20848: add condition to load only searchable field definitions

This makes FieldNotSearchable exception unnecessary.
Also replaced OutofBoundException with InvalidArgumentException for criterion.
EZP-20848: updated fixture and tests

OutOfBoundException is replaced with InvalidArgumentException.
Also fixture is updated as Field criterion now checks for searchable field only.
EZP-20848: updated Solr storage: check only searchable field definitions, replace OutOfBoundsException with InvalidArgumentException
EZP-20848: updated Search handler interface
EZP-20848: remove now unnecessary try/catch/throw
EZP-20848: update integrations tests expected exception
Fixed some PHPDoc issues
EZP-20848: remove deprecated TODO