Add back button for feature type reselection (closes #2453)

css/app.css

@@ -555,7 +555,7 @@ button.save.has-count .count::before {
     white-space: nowrap;
     text-overflow: ellipsis;
     overflow: hidden;
-    padding: 20px;
+    padding: 20px 20px 20px 40px;
 }
 
 .header button,
@@ -571,12 +571,19 @@ button.save.has-count .count::before {
     height: 100%;
 }
 
-.preset-list-pane .header button {
+.entity-editor-pane .header button.preset-close,
+.preset-list-pane .header button.preset-choose {
     position: absolute;
     right: 0;
     top: 0;
 }
 
+.entity-editor-pane .header button.preset-choose {
+    position: absolute;
+    left: 0;
+    top: 0;
+}
+
 .preset-choose {
     font-size: 16px;
     line-height: 1.25;

js/id/ui/entity_editor.js

@@ -24,6 +24,11 @@ iD.ui.EntityEditor = function(context) {
         var $enter = $header.enter().append('div')
             .attr('class', 'header fillL cf');
 
+        $enter.append('button')
+            .attr('class', 'fl preset-reset preset-choose')
+            .append('span')
+            .html('◄');
+
         $enter.append('button')
             .attr('class', 'fr preset-close')
             .call(iD.svg.Icon(modified ? '#icon-apply' : '#icon-close'));