added multimodal capabilities to the repo

[ugaetano]

I added multimodal capabilities to the repo.

Changelog:

• The skill will now render an APL document showing the fact on screen with a background image (only if the device supports APL)
• Added an array with URLs of the pictures
• Added a new file "aplDocument.json" has been added representing the rendered APL document
• The localization interceptor will now return the fact string and the image URL to load for every fact (only for the FACTS[] array)
• supportsInterface() and supportsAPL() helper functions added
• added an array with the