title: Drop rows in a dataframe where first column is a weekend date
body: <p>I have a <code>Dataframe</code> that looks like (e.g.) this:</p>
  
  <pre><code>print(df)
  
             date     high      low   close
  0    2008-01-01   15.540   15.540   15.54
  1    2008-01-02   15.750   15.210   15.25
  2    2008-01-03   15.450   14.950   15.02
  3    2008-01-04   14.990   14.400   14.48
  4    2008-01-05   14.890   14.400   14.78
  5    2008-01-06   14.890   14.400   14.78
  ....
  </code></pre>
  
  <p>I would like to remove the rows from the <code>Dataframe</code> whose date column contains a weekend date.</p>
  
  <pre><code>           date     high      low   close
  0    2008-01-01   15.540   15.540   15.54
  1    2008-01-02   15.750   15.210   15.25
  2    2008-01-03   15.450   14.950   15.02
  3    2008-01-04   14.990   14.400   14.48
  4 &lt;-- has been removed since 1/05/2008 is a Saturday   
  5 &lt;-- has been removed since 1/06/2008 is a Sunday
  ....
  </code></pre>
  
  <p>I tried this:</p>
  
  <pre><code>df = df[~df.date.dt.weekday_name.isin(['Saturday','Sunday']).any(0)]
  </code></pre>
  
  <p>but it doesn't work.</p>