Roles into their own controller. Rework interface. Add flash messages to ajax calls. Add description to roles. Possible to edit roles in use.

app/views/admin/roles/_users.html.haml

@@ -0,0 +1,20 @@
+.page-header
+  %h3 Users (#{users.length})
+- if users.present?
+  %table.table.table-striped.table-bordered.table-hover.datatable#users
+    %thead
+      %th.col-md-1
+      %th ID
+      %th Name
+      %th Email
+    %tbody
+      - users.each do |user|
+        %tr
+          %td.text-right
+            = hidden_field_tag "role[user_ids][]", nil
+            = check_box_tag @conference.short_title, @role.id, (@role.user_ids.include? user.id), method: :post, url: "/admin/conference/#{@conference.short_title}/roles/#{@role.name}/toggle_user?user[email]=#{user.email}&user[state]=", class: 'switch-checkbox', data: { size: 'small', off_color: 'warning', on_text: 'Yes', off_text: 'No' }
+          %td= user.id
+          %td= user.name
+          %td= user.email
+- else
+  %h5 No users found!