Changes

`EntityPersister.selectWhere` enhancement: possibility to declare a condition of an element property of a collection (declared as one-to-many for example).
Introducing `EntityCriteria.CriteriaPath` and `SerializableCollectionFunction`.
Extracting `EntityCriteria` from `EntityPersister` for improved readability and responsibility.
 (commit: ae26778)

Possibility to declare a projection by some method references in the select clause (to be enhanced)
 (commit: 23a5c32)

Code cleanup
 (commit: f6b9dae)

Possibility to declare a projection by some method references in the select clause: removing the `selectionProjectionWhere(Set<CriteriaPath>)` signature (previous commit) and introducing the SelectAdapter class, which is also used to configure simple Column addition to the Select clause. Hence, we have a single method signature to fulfil both needs.
 (commit: eb38872)

Simplifying data access for projected values:
 - allows data retrieval from the alias given to the projected column (see ProjectionDataProvider.getValue(String) and ColumnedRowIterator.convert(..))
 - allows building of a projected column through an entity property path (see `SelectAdapter.giveColumn(..)`)
 (commit: 35f70ac)