Added .pypirc authentication support for getting eggs

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extra : histedit_source : ebdc22b1f156f8af40265c5772addcfda6ae11d8
Add documentation

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extra : histedit_source : ff07b41a59ac22e1c05ce4fd42c6771378e80f13
fixes a bug where a Basic auth digest header can get encoded with newlines inside
Added tag 1.3.2 for changeset 076b472a9e3f
Bumped to 1.3.3 in preparation for next release.
For .svn legacy fallback, look for the files in the .svn not the directory.
   (Fixed unexpected deprecation warning from prombredanne)
Also removed the warning from fallback, only a deprecation warning is issued.
Environment.py whitespacing
Created a specialized command executor for tests in Environment.py
Legacy Test in test_egg_info now supresses the deprecation warning.
PythonPath is now explicitly controlled to allow setup.py test on clean
   python installations.  *Fixes Issue #101*
Moved some dummy svn tests from test_sdist to test_egg_info since
   they are egg_info tests.
Downgraded a with statement in a test since we haven't offically dropped
   2.4 support, however, maybe it is time.
Added a test case to ensure no extranuous output on sdist with a simple
   dummy package without rev ctrl.
Earlier Versions of python used gzip and tar directly.  So I need to
make sure they are in the paths for the legacy tests (why did it work before).
Let us hope that svn is not in that directory...
Merged pypa/setuptools into default
Correct changelog entry. Fixes #104.
Merged in philip_thiem/setuptools (pull request #24)

Issue #101 and tweak legacy fallback
Delint syntax

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extra : amend_source : 0f58aa917ebc71efd2904638fac3838fd0b0e4dd
Refactor for flatter code
Extract 'Credential' class for representing a username/password credential
Use 'expanduser' for better compatibilty.
Derive PyPirc from ConfigParser for more general purpose use.
Replaced __call__ with find_credential (for clarity of purpose). Removed dict_.
Get ConfigParser module from compat module for Python 3 compatibility.
Construct the 'creds' dictionary directly rather than building imperatively.
Renamed class for proper capitalization and for clarity.
Updated message when credentials used from .pypirc