eliminate sphinx warning about empty _static folder

Author: soxofaan

docs/images/basic_example.png renamed to docs/_static/images/basic_example.png

@@ -171,7 +171,7 @@ It can easily be converted into a pandas dataframe::
     dataframe.index = pd.to_datetime(dataframe.index)
     dataframe.dropna().plot(title='openEO NDVI with clouds')
 
-.. image:: images/timeseries.png
+.. image:: _static/images/timeseries.png
   :width: 400
   :alt: plotted timeseries
 

docs/images/timeseries.png renamed to docs/_static/images/timeseries.png

@@ -8,7 +8,7 @@
     :caption: Basic example
     :name: basic_example
 
-.. image:: ../docs/images/basic_example.png
+.. image:: ../docs/_static/images/basic_example.png
   :width: 500
   :alt: script result