Fix for nasty bug that happens when there are 2 or more schemas with tables that have the same name. Since all the AbstractPlatform classes get only the table name using ALL_* schema tables is dangerous because the owner is never supplied.

The other possible solution is to use the ALL_* tables but in each of the methods to fetch the owner before actualy querying them.

DDC-1282 - Remove overprotective casting of days/months to integer, which prevents passing columns as days. The platform is not responsible for escapsing, the DQL parser already does it way before generating the sql statements.

DBAL-112, DBAL-113 - Implement AbstractPlatform::getAlterSequenceSQL() and fix comparator code for sequences

[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