Merge pull request #488 from tjhance/test_pep352

add exception_hierarchy.txt which test/cpython/test_pep352.txt needs

test/cpython/exception_hierarchy.txt

+BaseException
+ +-- SystemExit
+ +-- KeyboardInterrupt
+ +-- GeneratorExit
+ +-- Exception
+      +-- StopIteration
+      +-- StandardError
+      |    +-- BufferError
+      |    +-- ArithmeticError
+      |    |    +-- FloatingPointError
+      |    |    +-- OverflowError
+      |    |    +-- ZeroDivisionError
+      |    +-- AssertionError
+      |    +-- AttributeError
+      |    +-- EnvironmentError
+      |    |    +-- IOError
+      |    |    +-- OSError
+      |    |         +-- WindowsError (Windows)
+      |    |         +-- VMSError (VMS)
+      |    +-- EOFError
+      |    +-- ImportError
+      |    +-- LookupError
+      |    |    +-- IndexError
+      |    |    +-- KeyError
+      |    +-- MemoryError
+      |    +-- NameError
+      |    |    +-- UnboundLocalError
+      |    +-- ReferenceError
+      |    +-- RuntimeError
+      |    |    +-- NotImplementedError
+      |    +-- SyntaxError
+      |    |    +-- IndentationError
+      |    |         +-- TabError
+      |    +-- SystemError
+      |    +-- TypeError
+      |    +-- ValueError
+      |         +-- UnicodeError
+      |              +-- UnicodeDecodeError
+      |              +-- UnicodeEncodeError
+      |              +-- UnicodeTranslateError
+      +-- Warning
+           +-- DeprecationWarning
+           +-- PendingDeprecationWarning
+           +-- RuntimeWarning
+           +-- SyntaxWarning
+           +-- UserWarning
+           +-- FutureWarning
+	   +-- ImportWarning
+	   +-- UnicodeWarning
+	   +-- BytesWarning