Point to active QR Code Projects in module description

This module isn't being supported any more it seems.

Can we get links to these with D8 support already:

• https://www.drupal.org/project/google_qr_code
• https://www.drupal.org/project/page_url_qr_code_block

And maybe these with just d7 support:

• https://www.drupal.org/project/barcode
• https://www.drupal.org/project/qrs_sheets
• https://www.drupal.org/project/mobile_codes