Removed setuptools import for --allow-site-packages

The only effect of the import is that ez_setup's use_setuptools() function
does a sys.exit(2) when the required version doesn't match the site package's
one.

If the import doesn't happen, use_setuptools() will just grab a matching
version if the site package's version is too old.

Note that the latest ez_setup.py scripts default to requiring the very latest
setuptools version! So --allow-site-packages isn't really very useful this
way.

bootstrap/bootstrap.py

@@ -75,12 +75,6 @@ try:
     from urllib.request import urlopen
 except ImportError:
     from urllib2 import urlopen
-if options.allow_site_packages:
-    try:
-        import setuptools
-        import pkg_resources
-    except ImportError:
-        pass
 
 ez = {}
 if os.path.exists('ez_setup.py'):