Revert "DEV: Migrate from {{user-selector}} to {{email-group-user-chooser}} (#94)" (#102)

The reverted commit pinned the plugin version on stable because the changes in that commit aren't compatible with stable. However, the version that we pinned the plugin to has a bug on stable and 50e62d84e8 fixes that bug. So we need to temporarily revert 5e24556b24 to unpin the plugin and I'll create another PR to undo this revert and re-pin the plugin version to this commit for sites on stable.

Meta topic: https://meta.discourse.org/t/data-explorer-editing-broken-on-stable/181274/11?u=osama.

.discourse-compatibility

@@ -1,2 +1 @@
-2.7.0.beta3: 9d86b8b653a6e4715d9a1e4a39537cd114f6c799
 2.6.0.beta2: 16873e708a3c924549e77f3fea011069358d1511

assets/javascripts/discourse/models/query.js.es6

@@ -47,10 +47,6 @@ const Query = RestModel.extend({
         newParams[name] = pinfo["default"];
       } else if (pinfo["type"] === "boolean") {
         newParams[name] = "false";
-      } else if (pinfo["type"] === "user_id") {
-        newParams[name] = null;
-      } else if (pinfo["type"] === "user_list") {
-        newParams[name] = null;
       } else {
         newParams[name] = "";
       }

assets/javascripts/discourse/templates/admin/components/q-params/user_id.hbs

@@ -1,8 +1,2 @@
-{{email-group-user-chooser
-  value=value
-  options=(hash
-    maximum=1
-  )
-  onChange=(action (mut value))
-}}
+{{user-selector usernames=value single="true"}}
 <span class="param-name">{{info.identifier}}</span>

assets/javascripts/discourse/templates/admin/components/q-params/user_list.hbs

@@ -1,5 +1,2 @@
-{{email-group-user-chooser
-  value=value
-  onChange=(action (mut value))
-}}
+{{user-selector usernames=value}}
 <span class="param-name">{{info.identifier}}</span>