Update Fancybox to version 3

One-sentence description

Update Fancybox to version 3

Why?

We currently use an old version (2.x). However, this version is licensed under CC BY-NC 3.0. Version 3 is GPLv3 for open source projects only. So I think this can be done only after fully open sourcing. Their website is unclear:

fancybox is licensed under the GPLv3 license for all open source applications. A commercial license is required for all commercial applications (including sites, themes and apps you plan to sell).

¿Our website is non-commercial but not open source?

Current implementation

Fancybox 2.x

Desired implementation

Fancybox 3.x