title: Remove duplicated rows
body: <p>I have read a <code>CSV</code> file into an R data.frame. Some of the rows have the same element in one of the columns. I would like to remove rows that are duplicates in that column. For example:</p>
  
  <pre><code>platform_external_dbus          202           16                     google        1
  platform_external_dbus          202           16         space-ghost.verbum        1
  platform_external_dbus          202           16                  localhost        1
  platform_external_dbus          202           16          users.sourceforge        8
  platform_external_dbus          202           16                    hughsie        1
  </code></pre>
  
  <p>I would like only one of these rows since the others have the same data in the first column.</p>