title: Matplotlib widget - many radiobuttons issue
body: <p>I need to set height of the matplotlib widget, change alignment or change font but i don't know how.</p>
  
  <p><strong>Screenshots:</strong></p>
  
  <p>5 radio buttons:
  <img src="https://i.stack.imgur.com/ju5D6.gif" alt="enter image description here"></p>
  
  <p>15 radio buttons:
  <img src="https://i.stack.imgur.com/1KZyF.gif" alt="enter image description here"></p>
  
  <p>And here is the critical code part:</p>
  
  <pre><code>def evolvecallback_(self, notification):
      global i
      stats={}
      results=[]
      fitnesses=[]
  
      for code,fit in evolve(i):
          results.append(code)
          stats[str(fit)]=code
          fitnesses.append(str(fit))
      i+=1
      fig = plt.figure() 
      done=""
  
      if found():
          done=" - Solution found!"
          print "Done!"
  
      fig.canvas.set_window_title("Generation "+str(i)+". - Best migrating individuals"+done) 
  
  
      ax = plt.subplot(111)
      ax.set_title(stats[str(fitnesses[0])])
      l, = ax.plot(x, s0, lw=2, color='blue')
      plt.subplots_adjust(left=0.4)
  
      axcolor = 'lightgoldenrodyellow'
      rax = plt.axes([0.05, 0.7, 0.15, 0.15], axisbg=axcolor)
  
      radio = RadioButtons(rax, tuple(fitnesses))
      def change(label):
          hzdict = {}
          x = np.arange(-5.0, 5.0, 0.01)
          j=0
          for i in tuple(results):
              hzdict[fitnesses[j]]=eval(i)
              j+=1
          ax.set_title(stats[str(label)])
          ydata = hzdict[str(label)]
          l.set_ydata(ydata)
          plt.draw()
      radio.on_clicked(change)
      plt.show()
  </code></pre>