Update README.rst

Author: Jim Bennett

README.rst

@@ -89,14 +89,14 @@ To interact with Azure IoT Hub, you will need to create a hub, and a register a
 
 You can find the device connection string by selecting the IoT Hub in the `Azure Portal <https://aka.ms/AzurePortalHome>`_, *selecting Explorer -> IoT devices*, then selecting your device.
 
-.. images/iot-hub-device.png
+.. image:: images/iot-hub-device.png
    :alt: Locating the device in the IoT hub blade
 
 *Locating the device in the IoT hub blade*
 
 Then copy either the primary or secondary connection string using the copy button next to the value.
 
-.. images/iot-hub-device-keys.png
+.. image:: images/iot-hub-device-keys.png
    :alt: Copy the primary connection string
 
 *Copy the primary connection string*