Document lite version and npm

[egirard]

Update readme to cover npm and lite version.

[ivodolenc]

Hi @egirard , I just bumped into this, since there are merged PR's that are supposed to separate the JS related code and the rest.

But looking at the import files, that doesn't make much sense since those calls are basically the same?

initPolyfill() are called in index.js and also in the index-lite.js (as well as proxy-animation and scroll-timeline-css).

Maybe I missed something here, but this code does not separate modules as one would expect, or at least I would expect this to be just an import scroll and view JS polyfill without proxy-animation and other similar code.

For proper code separation, I believe this should be completely rewritten, but some features that use CSS OM, such as animation ranges and others, cannot be implemented separately due to Timelines limits and design choices.

The correct way would be to just mention these things in the readme and inform users, no need for additional files.