The code used to call os.path.join to build a regex but without escaping
the backslash, which lead to test failures on Windows.  Antoine Pitrou
fixed it in 0a94e2f807c7 by enhancing the code to accept both / and \,
with proper escaping, but in my opinion this goes against the distutils
feature freeze, hence this change.

Distutils-based packages with C extension modules may fail because
Apple has removed gcc-4.2, the version used to build python.org
64-bit/32-bit Pythons.  If the user does not explicitly override
the default C compiler by setting the CC environment variable,
Distutils will now attempt to compile extension modules with clang
if gcc-4.2 is required but not found. Also as a convenience, if
the user does explicitly set CC, substitute its value as the default
compiler in the Distutils LDSHARED configuration variable for OS X.
(Note, the python.org 32-bit-only Pythons use gcc-4.0 and the 10.4u
SDK, neither of which are available in Xcode 4.  This change does not
attempt to override settings to support their use with Xcode 4.)

MERGE: And yet another emergency fix for #13803 bootstrap issue: Under Solaris, distutils doesn't include bitness in the directory name

And yet another emergency fix for #13803 bootstrap issue: Under Solaris, distutils doesn't include bitness in the directory name

MERGE: Emergency fix for #13803 bootstrap issue: Under Solaris, distutils doesn't include bitness in the directory name

Emergency fix for #13803 bootstrap issue: Under Solaris, distutils doesn't include bitness in the directory name

Bug reported by Hartmut Goebel and patch contributed by Carl Robben.
Carl tested the fix and we have a buildbot with rpm installed, so I’m
committing even though I could not run this test (but I do understand
the changed code :)

packaging.manifest.Manifest under Windows.  The "recursive-include"
directive now recognizes both legal path separators.

- Actually check the contents of the file created by bdist_dumb.
- Don’t use “RECORD” as filename for non-PEP 376 record file
- Don’t start method name with “_test”, it smells like a disabled test
  method instead of an helper method
- Fix some idioms (assertIn, addCleanup)