Simplify _build_install_args now that Python 2.6 is required.

ez_setup.py

@@ -336,13 +336,7 @@ def _build_install_args(options):
     """
     Build the arguments to 'python setup.py install' on the setuptools package
     """
-    install_args = []
-    if options.user_install:
-        if sys.version_info < (2, 6):
-            log.warn("--user requires Python 2.6 or later")
-            raise SystemExit(1)
-        install_args.append('--user')
-    return install_args
+    return ['--user'] if options.user_install else []
 
 def _parse_args():
     """