title: need to find every X minutes between to hours
body: <p>I have two hours lets say 12:00 and 14:00 (the input will always be two hours of "whatever" day) second time will always be greater than first time. So the input is simple : two given times in a day.  I need to find every 30 minutes between those two times.</p>
  
  <p>I need the following output (the ellapsed time between each output will always be 30 minutes in my case:</p>
  
  <p>12:00
  12:30
  13:00
  13:30
  14:00
  14:30</p>
  
  <p>I am discovering jodatime but I am a bit confused with how the determine "startTime" and "end Time"</p>