[DBAL-335] Fix nasty bug in MasterSlaveConnection, connecting and writing to slave when using keepSlave option.

Based on whether we are on 32 or 64 bit platform, postgres will return a string or an int for the expected php type of a bigint that is > 32 bits.

The AbstractSchemaManager expects getting the regex with its
delimiters since 8beb732f but the tests were not updated.

This is necessary because pdo_sqlsrv still has some little bugs that
prevent it from being used in all use-cases. Additionally only sqlsrv
can make use of the Azure federations features.

[DBAL-204] Sane refactoring of the previous idea. Removed a bunch of code again and implemented proper schema namespacing. Also got the wording right (hopefully) and fixed the algorithms.

[DBAL-195] Fix AbstractSchemaManagertests/Doctrine/Tests/DBAL/Functional/Schema/SchemaManagerFunctionalTestCase.phpdropAndCreateSequence

[DBAL-195] Fix AbstractSchemaManagertests/Doctrine/Tests/DBAL/Functional/Schema/SchemaManagerFunctionalTestCase.phpdropAndCreateSequence