EntityRepository::findBy should support multiple values on criteria fetching

Currently it is impossible to execute a multiple value findBy on EntityRepository.

So supposing we have a Foo entity, we can do this:

$foos = $em->getRepository('Foo')->findByName('value');

But it is impossible to do:

$foos = $em->getRepository('Foo')->findByName(array('value1', 'value2'));

We have most of the support done inside BasicEntityPersister, but the _getSelectConditionSQL restricts to a single value by doing:

$conditionSql .= ' = ?'; at line 1150

We can extend the support easily by detecting array value and adding an IN (...) condition on this case.