title: scipy.stats.expon.fit() with no location parameter
body: <p>I am using <code>scipy.stats.expon.fit(data)</code>  to fit an exponential distribution to my data. This appears to return two values where I would expect one.  The documentation <a href="http://docs.scipy.org/doc/scipy/reference/generated/scipy.stats.expon.html" rel="noreferrer">online</a> doesn't seem to say what <code>fit()</code> returns but looking at the source, I am guessing it is both a location and scale parameter. Can you fix the location parameter to <code>0</code> when doing the fitting?</p>