Declare support for Python 3.3 in 'setup.py'

Add 'tox' testing for Python 3.3.

CHANGES.txt

@@ -4,6 +4,8 @@ Changes
 1.3.1 (unreleased)
 ------------------
 
+- Declared support for Python 3.3 in ``setup.py``, and added ``tox`` testing.
+
 - When a non-retryable exception was raised as the result of a call to
   ``transaction.manager.commit`` within the "attempts" machinery, the
   exception was not reraised properly.  Symptom: an unrecoverable exception

setup.py

@@ -40,6 +40,7 @@ setup(name='transaction',
         "Programming Language :: Python :: 2.7",
         "Programming Language :: Python :: 3",
         "Programming Language :: Python :: 3.2",
+        "Programming Language :: Python :: 3.3",
         "Programming Language :: Python :: Implementation :: CPython",
         "Programming Language :: Python :: Implementation :: PyPy",
         ],

tox.ini

@@ -3,7 +3,7 @@ envlist =
 # Jython support pending 2.7 support, due 2012-07-15 or so.  See:
 # http://fwierzbicki.blogspot.com/2012/03/adconion-to-fund-jython-27.html
 #    py26,py27,py32,pypy,jython,coverage
-    py26,py27,py32,pypy,coverage,docs
+    py26,py27,py32,py33,pypy,coverage,docs
 
 [testenv]
 commands =