[ENH] Surveys : Some improvements for Tiki surveys

Avan.tech ticket: https://avan.tech/item67716

• [ENH] Surveys : Display all users associated to a choice and change stats rendering

• [ENH] Plugin Survey : Restrict admin users to one vote

• [ENH] Surveys : Add a restriction option to prevent admin users from voting more than once

This involves limiting the number of votes admin users can cast and making a few changes to the stats display: displaying users in relation to their choice of option and displaying the number of times they have selected that option.

Some screenshots:

Restriction option:

Stats: