Added some exception experiments I did.

They are to verify a detail we discussed with @qu1ck about a patch
for IBoM. They aren't very interesting, but they are a playground
to test Python 2/3 exception details.

experiments/exception/demo2.py

@@ -0,0 +1,9 @@
+###########
+# Python 2:
+###########
+try:
+    raise Exception
+except Exception as e:
+    s, r = getattr(e, 'message') or str(e), getattr(e, 'message') or repr(e)
+    print 's:', s, 'len(s):', len(s)   # noqa: E999
+    print 'r:', r, 'len(r):', len(r)   # noqa: E999

experiments/exception/demo3.py

@@ -0,0 +1,7 @@
+#!/usr/bin/python3
+try:
+    raise Exception
+except Exception as e:
+    s, r = getattr(e, 'message', str(e)), getattr(e, 'message', repr(e))
+    print('s:', s, 'len(s):', len(s))
+    print('r:', r, 'len(r):', len(r))

experiments/exception/test.py

@@ -0,0 +1,21 @@
+import logging
+
+logging.basicConfig(level=logging.DEBUG)
+
+
+class ETest(Exception):
+    pass
+
+
+try:
+    raise ETest("Hi!")
+except ETest as e:
+    print(e)
+    print(repr(e))
+    print(type(e))
+    print(e.__dict__)
+    logging.debug(e)
+    logging.error(e)
+    logging.warning(e)
+    logging.info(e)
+    logging.critical(e)