Suppress output when checking viability of wget/curl. Fixed viability assignment and Windows platform detection.

Issue #63: Initial implementation of a mechanism for securely bootstrapping setuptools, leveraging system tools for trust validation.

Issue 60: Implemented experimental opt-in support for using native launchers rather than installing launcher executables. My initial experience with this technique has been very positive.

Replaced overly-specific error messages with more general ones for improved cross-implementation compatibility. Fixes #50.

Issue 50: Removed filename and line number from SyntaxErrors returned by invalid_marker. This change simplifies the test and paves the way for supporting PyPy.

Removed section on Managing Multiple Projects. It only works for Subversion, which is substantially replaced by other SCM systems.

Corrected syntax in setuptools documentation around console scripts with extra requirements. Fixes #62.

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extra : rebase_source : 79c95e70593d4e4177c3c1f9625e427d9ce0a16c

Use a pattern object to invoke the substitution in _adjust_header, restoring Python 2.4-2.6 compatibility.

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