title: Complex "Contains" string comparison
body: <p>I'm developing a C# 4.5 app and I need a function to return true for the following comparison:</p>
  
  <blockquote>
    <p>"bla LéOnAr d/o bla".ComplexContains("leonardo")</p>
  </blockquote>
  
  <p>In other words, I need <code>string.Compare(str1, str2, CultureInfo.InvariantCulture, CompareOptions.IgnoreCase | CompareOptions.IgnoreSymbols | CompareOptions.IgnoreNonSpace)</code> to also check for "contains!</p>
  
  <p>Can anyone help?</p>