title: Skip gcf().autofmt_xdate() at pandas plot creation
body: <p>I'm trying to plot multiple time series using a pandas dataframe. The dataframe contains more than 100 registers.</p>
  
  <p>From the panda's documentation I've read that when pandas.df.plot() is executed this is also executed with gcf().autofmt_xdate(). I want to put my custom datetime format but when I tried my custom date format is overlapped over the date given by default by pandas plot. ¿Is there a way to skip gcf().autofmt_xdate() on plot creation? ¿How can i provide to panda a custom datetime format?</p>
  
  <p>Here is the generated plot.</p>
  
  <p><img src="https://i.stack.imgur.com/1ZZax.png" alt="enter image description here"></p>
  
  <p>Here is the python code.</p>
  
  <pre><code>import matplotlib.pyplot as plt
  import matplotlib.dates as mdates
  import pandas as pd
  from pandas import Series
  import pickle
  datos = pickle.load(open("datos_reporte.pickle", "r"))
  reload(plt)
  series_o = []
  series_p_h = []
  series_p_d = []
  series_names = []
  for cod_estacion in datos.keys():
      x = [d[0] for d in datos[cod_estacion]['historial_semanal']]
      y = [d[1] for d in datos[cod_estacion]['historial_semanal']]
      s = Series(y, x)
      series_o.append(s.groupby(level=0).first())
  
  df1 = pd.concat(series_o, join='outer', axis=1)
  interval  = int(len(df1) / 12)
  df1.columns = series_names
  ax = plt.figure(figsize=(7,5), dpi=100).add_subplot(111)
  df1.plot(ax=ax)
  ax.xaxis.set_major_locator(mdates.HourLocator(interval=200))
  ax.xaxis.set_major_formatter(mdates.DateFormatter('%m/%d-%H:%S'))
  ax.xaxis.grid(True, which="minor")
  plt.title("Datos observados")
  plt.ylabel('Caudal m^3/s')
  plt.xlabel('Fecha')
  plt.legend(loc=0,prop={'size': 7})
  plt.xticks(rotation='vertical', fontsize = 8)
  plt.subplots_adjust(bottom=.2)
  plt.show()
  </code></pre>