[Fiware-developer-experience] CPr and sensors

[David Muriel]

Hi,

We've added an example of Context Provider configuration and use to
devguide.  The example is quite simple and it's not directly coupled
with the restaurants, as that would require adding and extra layer of
complexity into devguide.  You can find the example and how to use it
on the file https://github.com/Bitergia/fiware-devguide-app/blob/master/doc/ContextProvider.md.

Also, we've added the option to automate the sensors creation at
container startup time.  There's two new environment variables in the
compose file to enable this:

- SENSORS_GENERATION_ENABLED:  Setting this to true will create and
initialize the sensors for each restaurant.  Please note that this is
takes some time to complete, so the devguide container will not be
ready until this process completes.  This can be done manually via the
server/feeders/sensorsgenerator.js script.

- SENSORS_FORCED_UPDATE_ENABLED:  Setting this to true will force an
update of all the created sensors, randomly varying the value of each
sensor.  This can be done manually via the
server/feeders/sensorsupdater.js script.

It is also advisable to enable subscriptions via
ORION_SUBSCRIPTIONS_ENABLED so that devguide adds the sensors readings
to each restaurant every time the sensors are updated.

Regards,

-- 
David Muriel.