Backport new features into the interactive template

[alykat]

No description provided.

[DanielJWood]

Update LESS package in the interactive template to avoid issues in the future. Per this commit: 9ab4c21

When trying to use this css file from maplibre, less.js choked on a couple different pieces of code that are from the most recent release of CSS. Updating LESS to version 4+ solved this issue.

[DanielJWood]

Use getRemote() function from this project's s3.js helper library. See here: Chalkbeat/interactive-template#5

[DanielJWood]

In the lazy loading area, I created an "isBackwards" flag that tells you which direction you came from:

var isBackwards = index < all.indexOf(previous) ? true : false;