Adding a transition to change background images

[brunoamuniz]

Is your feature request related to a problem? Please describe.

I am to make a smooth background transition for the new sample application

Describe the solution you'd like

Prototypes are available here https://xd.adobe.com/view/ee40c281-7923-4cc4-a90a-105f81355707-bb13/screen/9eab7f98-c4f7-4a4d-bf6c-1d8e5dfe3710/

We will apply this prototypes here https://github.com/TotalCross/HomeApplianceXML

Describe alternatives you've considered

It needs to work properly on all devices, not only Linux ARM

Devices

Any device, but I will test it on Android and my Raspberry Pi

Additional context

Add any other context or screenshots about the feature request here.

[brunoamuniz]

Also need to provide a doc showing how to do it =)