title: MonoDevelop can't import VS2013/2015 solutions
body: <p>I'm opening a <code>.sln</code> file that I transferred from VS2013 into MonoDevelop. When I attempt this, however, it gives me the following error(s):</p>
  
  <pre><code>1. Project 'foo' has a different ToolsVersion than the containing solution.
  2. Error while trying to load the project '/path/to/foo.csproj': Unknown ToolsVersion '12.0'
  3. [repeat 2 for every project in the solution]
  </code></pre>
  
  <p>When I tried doing this for a VS2015 file, it game me the same errors, except this time <code>ToolsVersion</code> was <code>14.0</code>.</p>
  
  <p>My MonoDevelop version is v4.0.12; is there a workaround for this?</p>