title: Boost class serialization, change in member types
body: <p>How does one handle switching the type of serialized members while retaining compatability with previous archive?  E.g. I want to change <code>float/int</code> to <code>double/size_t</code>.</p>
  
  <p>I know I can increment version number but that makes code messy.  Is there a different way to handle that?  If it makes difference, the members are serialized thru <code>MAKE_NVP</code>. </p>