[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.

DBAL-88 - Change index retrieval of MySQL to use information_schema.statistics which avoids errors when using reserved words for table names (for example in database driver).

DBAL-84 - Fix VARCHARs being silently set to 255 chars when larger than Maxlength. Now they are converted to Text/CLOB fields automatically. Refactored the VARCHAR code considerably.

[DBAL-42] Add support to reverse engineer Comments from MySQL, PostgreSQL and ORacle into Doctrine\DBAL\Schema\Column instances and added comment comparison into Comparator.

DBAL-62 - There is a diference between maximum length (now 4000, oracle is the smallest possible denominator here) of varchars and the default length (255).

added supportsReleaseSavepoints(), disabled releasing for Oracle and DB2 (already disabled for MSSQL

added supportsReleaseSavepoints(), disabled releasing for Oracle and DB2 (already disabled for MSSQL

Added registerDoctrineMappingType() and getDoctrineMappingType() methods, converted DB2 platform and added some tests, made all platforms work for now

Support Sqlite

Migrated MySQL to Doctrine Type Map

Fixed nasty bug in testcase

Migrated Postgres to support Doctrine Mapping Types

Refactored Oracle Platform to support Doctrine Mapping Types

Refactored DB2 support for Doctrine Mapping Types a little bit

Fixed pecl/ibm_db2 Driver and Connection to run smoothly against the complete test-suite (depending on a c-patch to the extension though)

DDC-496 Finished first versions of platform and schema manager for DB2, DDC-528 Added support for PDO_IBM driver, passing all but 3 tests that are related to CLOB fields