[2.0] Fix for test suite. It was trying to recreate association tables and they're not getting deleted. SchemaTool was trying to recreate them during some executions.

[2.0] Added functionality to convert a Doctrine 1 schema to Doctrine 2 to help users with upgrading. Lots of other small bug fixes and changes.

[2.0] Some work over SchemaTool update of schema (affects directly the CLI schema-tool task on --update option.

[2.0] Various necessary fixes and adjustments for oracle as well as fixes for better handling of temporal types. Closed #2452.

[2.0] Made MySqlPlatform default to innodb table engine. Some cleanups while investigating the optimistic locking failures.

[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] Test coverage for OFFSET AND LIMIT sql generation for all platforms and Query class with setFirstResult() and setMaxResult()

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

[2.0] Changed identifier quoting strategy to something simpler. Dropped Doctrine prefix from annotations.

[2.0] More general work on the SchemaManager and Platform classes. Making API more complete and adding sqlite and mysql test coverage.

[2.0] Fixes and enhancements to sequence generators. Test suite now runs & passes against postgres. Other minor, unrelated cleanups.