Onboarding Page
             The {@code OnboardingPage} is used by the Onboarding Fragment to display an image and a short text. 
Use this class to show a different number of pages in the Onboarding Screen. Customizing the default onboarding pages can be done via overriding of app resources.
 When using the Screen API set an java.util.ArrayList containing {@code OnboardingPage} objects as the EXTRA_IN_ONBOARDING_PAGES when starting the CameraActivity . 
 When using the Componenent API provide an java.util.ArrayList containing {@code OnboardingPage} objects as the argument for the Onboarding Fragment factory method  or  . 
Constructors
Create a new onboarding page with the desired string resource and drawable resource.
Note: the string should be a short sentence.
Internal use only.
Internal use only.
Functions
Properties
Internal use only.