geom_path generates warrning message after updating R
<p>I installed a R version 3.3.2 and I have a problem since that. I get following warning messages:</p>

<p>1: <code>panel.margin</code> is deprecated. Please use <code>panel.spacing</code> property instead
2: Removed 28 rows containing missing values (geom_path).</p>

<p>Example code:</p>

<pre><code>require(ggmap)
require(ggplot2)
from &lt;- 'London'
to &lt;- 'Paris'
route_df &lt;- route(from, to, structure = 'route', mode = 'driving')
qmap('London', zoom = 10) +
  geom_path(
    aes(x = lon, y = lat),  colour = 'red', size = 1.5,
    data = route_df, lineend = 'round')
mapdist(from, to)
</code></pre>

<p>Any suggestions?</p>