[2.0] Extracting Doctrine 1 schema conversion from orm:convert-mapping task to a orm:convert-d1-schema task

[2.0][DDC-426] Fixed issue with CliController that never notifies if run() executed successfully or not.

[2.0][DDC-92] Fixed. Patch provided by Christian Heinrich. [DDC-274] Started some method renaming. [DDC-142] Fixed (join column names and discriminator column names dont support quoting) [DDC-258] Fixed.

[2.0][DDC-364] Added Doctrine\Common\Version which provides the current version of Doctrine. Also added CLI tasks for Common and DBAL, since they may vary in the future.

[2.0] Incorporated CLI refactorings. Added support to namespaces and unlimited depth namespaces. Dropped globalArguments for now, since they interfer in DAG implementation.