Remove tree-shaking possibility (broken)

[jdeniau]

Sadly reverting tree-shaking possibility (#1888) as it does break. Moreover, as nearly every collection type can be converted to another collection (Map().toList() for example), so nearly no code was removed.

I think that if we want to implement this, we might need to rethink this functionality.

[jdeniau]

@bdurrer I willl merge this quickly to make v5 functional, but I would really appreciate your opinion on this.

For the record the sideEffects I set was wrongly set to "./src/CollectionImpl.js" instead of "./dist/es/CollectionImpl.js"

Once you include CollectionImpl, then all .toXXX methods are implemented and the bundle size goes back to 17ko instead of 18ko (full bundle), so nearly no gain.
Even with the CollectionImpl as side effect, I had on issue on this code

where Collection is undefined.