title: Turn columns to rows in pandas
body: <p>I have a dataframe with the names of newborn babies per year.</p>
  
  <pre><code>"name","1998","1999","2000","2001","2002","2003","2004","2005","2006","2007","2008","2009","2010","2011","2012","2013"
  "Aicha",0,0,0,0,0,0,0,0,0,0,0,0,10,0,0,0
  "Aida",15,20,16,0,10,0,10,14,13,11,12,11,13,14,13,18
  "Aina",0,0,0,0,0,0,16,12,15,13,12,14,10,11,0,12
  "Aisha",14,0,10,12,15,13,28,33,26,26,52,44,43,54,68,80
  "Ajla",15,10,0,0,22,18,28,27,26,26,19,16,19,22,17,27
  "Alba",0,0,14,14,22,14,17,19,23,15,28,32,25,33,33,33
  </code></pre>
  
  <p>I want to plot this in a line chart, where each line is a different name and the x axis is the years. In order to do that, I imagine I need to reshape the data into something like this:</p>
  
  <pre><code>"name","year","value"
  "Aicha","1998",0
  "Aicha","1999",0
  "Aicha","2000",0
  ...
  </code></pre>
  
  <p>How do I reshape the data in that fashion? I've tried <code>pivot_table</code> but I can't seem to get it to work.</p>