Image and text attribution in books

[pserwylo]

All generated books need to include attribution for text.

Simple Wikipedia pages all include this text in the footer of each page:

Text is available under the Creative Commons Attribution/Share-Alike License and the GFDL; additional terms may apply. See Terms of Use for details.

Images all come from Wikimedia Commons, and each is licensed individually. However most are CC BY-SA 3.0. I believe the metadata can be obtained via an API.

All attribution should:

• Recorded in the corresponding WikiImage database table (for images)
• Recorded in the corresponding WikiPage database table (for text)
• Shown in the generated PDF (perhaps in a final page which summarises all attribution for the entire book).
• Added as a menu item when viewing the book.

[pserwylo]

This has been completed for the mobile app, but doesn't include attribution in the generated PDFs yet.