[2.0][DDC-49][DDC-50][DDC-33] Fixed DDC-49 and DDC-50. Also addressed DDC-33. Various other small changes and fixes. For problems with proxy objects please refer to the updated documentation.

[2.0] Fixed several referential integrity issues. Fixed critical issue with inserts being run twice on postgresql/oracle. Added support for additional tree walkers that modify the AST prior to SQL construction and started to play with it in a testcase.

[2.0] Streamlined result structures. Hydration improvements: Small overall improvements, large improvement for (joined) fetched collections (~60%). 

[2.0] completed implementation of lazy loading for Collections. Created debug helper class. Fixed default for orderBy clause to ASC

[2.0] Moved locking tests into Functional namespace. Fixed several missing flush() calls in some functional association tests. Reordered DELETE statements for ecommerce model tests in OrmFunctionalTestCase in order to maintain referential integrity. Fixed issue with bi-directional self-referencing one-one associations. Some other small improvements and cosmetics. Small hydration performance improvement through inlining method call in UnitOfWork::createEntity().

[2.0] Introduced SQL logging facilities. Made Type constructor private to prevent instantiation and force use of the factory method getType().

[2.0] Started to implement proxy object handling. Introduced a configuration switch for partial objects (allowPartialObjects) that defaults to TRUE. Setting to FALSE enables proxying and lazy-loading.

First tests for basic collection implementation. First experimental use of closures (Currently commented out, because the svn server makes a syntax check against 5.2.x).