[2.0] Some code reordering, changes. Removed classMetadata from RangeVariableDeclaration, since it is against AST concept.

[2.0] Removed AssociationMappings from ResultSetMapping  for improved caching. Fixed caching issue with reflection classes and properties. Reimplemented and leaned up broken identifier quoting. Added support for named (native) queries. Fixed small hydration memory leak.

[2.0] More docblocks. Renamed methods Type::addCustomType to Type::addType and Connection::exec to Connection::executeUpdate. Added Type::hasType.

[2.0] Implemented DQL bulk UPDATE support for Class Table Inheritance. Corrections to MultiTableDeleteExecutor and SqlWalker. DQL bulk UPDATE support not yet fully complete.

[2.0] Implemented DQL bulk DELETE support for Class Table Inheritance. Other cleanups, refactorings and docblock additions.

[2.0] Moved code between Query and AbstractQuery. Added first NativeQuery implementation. Hydration work and code movements for discriminator column usage. Started implementing Single Table Inheritance.

[2.0] Parser work. Drafted logic for multi-table deletes through DQL (for Class/Concrete Table Inheritance)

[2.0] Parser work. Drafted logic for multi-table deletes through DQL (for Class/Concrete Table Inheritance)