only require ntlm if ntlm auth was requested.

fixes savonrb/savon#819

lib/httpi/adapter/net_http.rb

@@ -18,7 +18,7 @@ class NetHTTP < Base
 
       register :net_http, :deps => %w(net/https)
       def initialize(request)
-        check_net_ntlm_version!
+        check_net_ntlm_version! if request.auth.ntlm?
         @request = request
         @client = create_client
       end

spec/httpi/adapter/net_http_spec.rb

@@ -132,6 +132,15 @@
         to raise_error(HTTPI::NotSupportedError, /Net::NTLM is not available/)
     end
 
+    it 'does not require ntlm when ntlm authenication is not requested' do 
+      HTTPI::Adapter::NetHTTP.any_instance.stubs(:check_net_ntlm_version!).raises(RuntimeError)
+      request = HTTPI::Request.new(@server.url)
+
+      expect(request.auth.ntlm?).to be false
+
+      expect { HTTPI.get(request, adapter) }.not_to raise_error
+    end
+
     it "does not crash when authenticate header is missing (on second request)" do
       request = HTTPI::Request.new(@server.url + 'ntlm-auth')
       request.auth.ntlm("tester", "vReqSoafRe5O")