DbFactoryBase: CreateCommand without transaction is now overload of CreateCommandWith
Introduced GenericProcessorBase and let SqlServer2000Processor derive from it
SqlServerProcessor derives from GenericProcessorBase
OracleProcessors derive from GenericProcessorBase
Make SqlServerCeProcessor derive from GenericProcessorBase
SqlLiteProcessor derives from GenericProcessorBase
Add same mechanics to JetProcessor and implement missing Exists
FirebirdProcessor now derives from GenericProcessorBase
MySqlProcessor derives from GenericProcessorBase
PostgresProcessor derives from GenericProcessorBase and remove duplication "Beginning transaction" message
Merge branch 'Processoritis' into transaction-per-migration-take2
Moved all mayor exceptions to core and derive indirectly from exception instead of ApplicationException fixes #360
Done main work for transaction per migration
Removed any unnecessary opening and closing of transaction or connections and fixed tests close #178
Taskexecutor disposes processor to ensure connection close and transaction rollbacked if any
Fixed weird announcing of BeginTransaction and Commit transaction, due to wrongly placed announcer messages, fixed transaction management on up and down

and made begintransaction fool proof
Refactor Transactionless into TransactionBehavior enum
Make sure taskexecutor calls processor dispose no matter what

& Fix incorrect connection usage in integrationtestbase
Fix one processor test for Postgres

Needed a BeginTransaction call.
Fix all FirebirdProcessor tests

Call Processor.BeginTransaction instead.