Create autocomplete widget where you cannot add new terms for MESH

I think I have solved the problem with searchable tags for MESH Medical Subject Headings https://www.ncbi.nlm.nih.gov/mesh/

We shall copy the entire MESH system tree into the MESH vocabulary in medicdebate.

Every publication in https://www.ncbi.nlm.nih.gov is classified according to MESH already.

Ordinary users should not be allowed to add new termas via the autocomplete widged. Thatr would lead to cause, but they can write a term, and then get suggestions from MESH.

They shall also be able to choose multile terms.

When we add a demosocracy or delegated voting module, this one shall correspond to the MESH tree, so that delegatescan choose on which level of the tree they wish to be delegable.

Only admisn should be allowewd to add new terms.