title: Issue plotting vertex labels using igraph in ipython
body: <p>I usually work in a IPython notebook, which I open on Windows with the command</p>
  
  <pre><code>ipython qtconsole --matplotlib inline
  </code></pre>
  
  <p>I'm currently using IPython QtConsole 3.0.0, Python 2.7.9 and IPython 3.0.0.</p>
  
  <p>I want to plot a graph, together with its labels</p>
  
  <pre><code>from igraph import *
  g = Graph.Lattice([4,4],nei=1,circular=False)
  g.vs["label"]=[str(i) for i in xrange(16)]
  plot(g, layout="kk")
  </code></pre>
  
  <p>In this way, I obtain a inline plot of the graph, but there are <strong>no</strong> labels and I get the following message error for each of the missing labels</p>
  
  <pre><code>link glyph0-x hasn't been detected!
  </code></pre>
  
  <p>where x is some integer number.</p>
  
  <p>I also tried to specify the labels directly inside the <code>plot()</code> command, using <code>vertex_label = ...</code>, but nothing works.</p>
  
  <p>It seems to me that the labels are defined correctly and that the problem reside in the ipython notebook and/or in the modules it uses to plot the graph. Can anyone kindly help me with this issue?</p>
  
  <p>I also tried all possible figure formats SVG and PNG, using the commands below, but the problem remains.</p>
  
  <pre><code>%config InlineBackend.figure_format = 'svg'
  %config InlineBackend.figure_format = 'png'
  </code></pre>