[Lists] Search/suggestion on ES side rather than locally

First, great project guys, thanks a lot for all your work on this!

**Affected Projects**
React

**Is your feature request related to a problem? Please describe.**
The Multilist search is limited to the set of elements in the list (`size` param).

**Describe the solution you'd like**
It would be great to have a way to enable the search feature on MultiLists to do a server search instead of a local search and with something like `strictSelection` enabled it should be possible to add selected suggested items to the list.

**Describe alternatives you've considered**
- increasing `size`: my index is too big to fit and it would make the UX sluggish
- I have tried to disable search on the MultiList and use a DataSearch component instead. I guess this could be a solution but it is not great from a UX perspective (and I hit another problem which I will report in a separate issue).

A related issue: https://github.com/appbaseio/reactivesearch/issues/515
However, the "load more" feature does not solve the problem since it does not seem to filter/search (also does not work on my side - will create a separate issue as well).