re #91 : Get default session lifetime from session.gc_maxlifetime
re #91 : Refactor KExceptionHandlerInterface

- Rename setErrorLevel() to setErrorReporting()
- Rename getErrorLevel() to getErrorReporting()
re #91 : Add 'auto_connect' config option to DatabaseAdapterAbstract. If TRUE, database will connect when the adapter is constructed. Default is FALSE.