feat add driver class

driver need to separate oci calls form high level logic and for
better testability
feat add driver class configuration entry
feat (Database.php) add driver reference and getter
feat (Statement.php) add driver reference
feat (OCIDriver) add functionality
feat (DriverInterface) add Interface for driver
feat migrate to driver interface
fix Database Exception to be simple child of \Exception
feat (Statement.php) add bindColumn method
style (Statement) restyle
fix (Statement) simplify code
style (Statement) code reformat
style (Database) code reformat
feat (Database) add shortcuts for statement fetch* methods
feat (Profiler) add profile structure class
fix (Database) profiler phpdoc type
feat (Statement) remove all oci deps
fix (Statement) execute describe should be available anytime
refactor remove invalid tests
refactor autoload string replace with namespace