allow passing cert/ssl information to urllib2.urlopen and httplib.HTTPSConnection

This is basically a backport of issues #9003 and #22366.
diff --git a/Lib/test/selfsigned_pythontestdotnet.pem b/Lib/test/selfsigned_pythontestdotnet.pem
new file mode 100644
index 0000000..9a80073
--- /dev/null
+++ b/Lib/test/selfsigned_pythontestdotnet.pem
@@ -0,0 +1,16 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----