update README

Author: Jovan Mitrevski

README.md

@@ -9,4 +9,6 @@ In order to use matplotlib plots with QtQuick, do the following:
 1. In your QML files, instantiate an object with the QML type defined above. Its `objectName` property specifies the name of the object that can be found in the QML engine. It can be retrieved in python with `win.findChild(QtCore.QObject, "spectFigure")`, for example, where `"spectFigure"` is the `objectName` in this case.
 1. One can then pass this object as needed. This is the FigureCanvasQtQuickAgg object. The figure can be found in its `figure` property.
 
+The test in the tests directory gives a simple example of how to use this package.
+
 Please let me know if you have any suggestions or better ways I should do this.