title: Determining the the Length of a Date Range Overlap
body: <p>I have a constraint that I have two date ranges. One of them will never change it is a measurement period (Date Range A). I need to try and find if the second Date range (Date Range B) Overlaps with A for a length of at least 6 months. What would be the best way to go about this?</p>
  
  <p>I have considered trying to compare the start and end dates of the two ranges in different ways depending on how the two intersect, but have yet to hit upon a solid methodology. </p>