Fix obvious typo
Lighten by avoiding unecessary calls to $.proxy
Add missing periods
Rename variable to avoid confusion
Fix bug where callbacks passed upon initialization are ignored
Instead of overriding open, provide a chainable afterOpen for imageGallery
Simplify code
rename featherlight-prev to featherlight-previous
Factorize navigation creation
Create navigation only once
Use events for previous/next image
Use <span> instead of <em>
Use detectSwipe if available