title: reading a file in common lisp
body: <p>How do i read the following file which has columns of data with header and space or tab delimited, in common lisp.</p>
  
  <p>I also wanted to put the data in to list of list which contains rows.</p>
  
  <p>Also how to get the difference in dates in common lisp</p>
  
  <p>ID YR MO DA YrM MoM DaM<br>
  100 2010 2 20 2010 8  30<br>
  110 2010 4 30 2010 9  12<br>
  112 2010 8 20 2010 10 20   </p>