Add --version option for futurize script (issue #57)
Don't hard-code python interpreter path.
Fix deprecated unittest usage in Py3.
Don't run clearly Py2 tests on Py3.

These are only stage 1 futurizations, which don't guarantee Py3
compatibility, so don't run them.
Add list of contributors to docs/credits.rst
Be explicit about encoding file contents as UTF-8 in unit tests (issue #63)
Bump version number to v0.12.3-dev and add What's New entry for v0.12.3
Add ``--version`` option to ``pasteurize``
Mark known-failing tests of ``past`` on Py3 as @expectedFailurePY3
Test on Python 3.4
Add Python 3.4 classifier
Tests: add missing imports and more xfail decorators
Merge branch 'frewsxcv-master' into v0.12.x
Disable travis-ci tests on Py2.6 for now to reduce noise
Update What's New section for v0.12.3
Fix ensure_new_type's handling of longs.

This handles ints as input, but not longs, which causes test failures on
32-bit systems (and possibly 64-bit if you pick a large enough number).
Fix past standard_library hook test.

The test framework here calls remove_hook() from past, but the test
installs hooks from future, so they bleed through.
Fix exception handling in test.support.bind_port.

In Python 3.3, exceptions on sockets raise OSError, but since this code
is a backport for 2.x, it needs to use the previous exception type,
namely, socket.error.