title: StructureMap can't register open generics with default convention properly
body: <p>I am trying to register all my open generic types with default convention.
  If I use default convention like below I can confirm that my type is registered correctly.</p>
  
  <p>However when I try to resolve it it throws following error.</p>
  
  <p>No default Instance is registered and cannot be automatically determined for type 'IGenericClass'</p>
  
  <pre><code> public DefaultRegistry()
          {
              Scan(
                  scan =&gt;
                  {
                      scan.AssembliesFromApplicationBaseDirectory(
                          a =&gt; a.FullName.StartsWith("StructureMapApp"));
                      scan.WithDefaultConventions();
                  });
          }
  
  var container = new Container(x =&gt;
      {
          x.AddRegistry(new DefaultRegistry());
  
      });
      container.WhatDoIHave();
  
      var result = container.GetInstance&lt;IGenericClass&lt;DummyClass&gt;&gt;();
  </code></pre>
  
  <p>Here is the container.WhatDoIHave() result
  container.WhatDoIHave()<a href="https://i.stack.imgur.com/rs6hX.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/rs6hX.png" alt="enter image description here"></a></p>
  
  <p>If I register it by explicitly it works as expected.</p>
  
  <pre><code>       container.Configure(x =&gt; x.For(typeof(IGenericClass&lt;&gt;)).Use(typeof(GenericClass&lt;&gt;)));
          var sad = container.GetInstance&lt;IGenericClass&lt;DummyClass&gt;&gt;();
  </code></pre>
  
  <p>Here is container.WhatDoIHave() result       </p>
  
  <p><a href="https://i.stack.imgur.com/cnUIN.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/cnUIN.png" alt="enter image description here"></a></p>
  
  <p>As you may notice there is a slight difference between two registries.The registry made with default convention includes assembly and model name while explicit one doesn't have.</p>
  
  <p><a href="https://i.stack.imgur.com/OTlQi.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/OTlQi.png" alt="enter image description here"></a></p>
  
  <p>Is there any way Auto register all open generics without explicitly provide all of them ?</p>