[test] loading regression in 0.10.6

closing GH-230

Author: kares

src/test/ruby/test_digest.rb

@@ -116,4 +116,12 @@ def test_098_features
     assert_equal(sha512_a, encode16(OpenSSL::Digest::SHA512.digest("a")))
   end
 
+  def test_net_ssh_like_loading
+    require 'openssl'
+    require 'openssl/digest'
+    # shout not raise TypeError: superclass mismatch for class Digest
+    assert OpenSSL::Digest.is_a?(Class)
+    assert OpenSSL::Digest("MD5")
+  end
+
 end