Adding doctrine-dbal to composer.json and making it work just like doctrine command (from Doctrine ORM)

[DBAL-45] Add reserved keywords feature through platforms and as a validator for any Schema instance with subelements. Add Command to check for reserved keywords in current database.

DDC-684 - Fix flaw in build process, DBAL PEAR package now does not contain Common code and just adds a dependency on the PEAR channel. Additional full package is generated into dist/

DDC-515 - Enhanced Validate-Schema-Command, integrated it with CLI and besides mapping<->database checks also do consistency checks of the mapping files

[2.0] Fix bug in detection of global Doctrine Cli Configuration finding the empty replacement configuration before the correct one.

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

[2.0][DDC-122][DDC-97][DDC-98][DDC-147] Refactored metadata mapping drivers by removing the useless PRELOAD mode. Introduced ClassMetadataFactory#getAllMetadata. Classloader simplifications. Old classloaders deprecated. New Doctrine\Common\ClassLoader is almost the same as the previous IsolatedClassLoader.