fix overflow in commit dialog.

css/app.css

@@ -948,11 +948,11 @@ div.typeahead a:first-child {
     border:1px solid #ccc;
     background:#fff;
     max-height: 160px;
-    overflow: visible;
 }
 
 .commit-modal .warning-section .changeset-list  {
     margin-right: 20px;
+    overflow-x: visible;
 }
 
 .commit-section.modal-section {
@@ -961,15 +961,6 @@ div.typeahead a:first-child {
 
 .commit-section.modal-section:last-child { padding-bottom: 20px;}
 
-.commit-modal .changeset-list li {
-    position: relative;
-}
-
-.commit-modal .changeset-list li button {
-    position: absolute;
-    right: -30px;
-}
-
 .modal-section {
     padding: 20px;
 }

js/id/ui/commit.js

@@ -86,6 +86,7 @@ iD.ui.commit = function(map) {
             .on('click.cancel', function() {
                 event.cancel();
             });
+            cancelbutton.append('span').attr('class','icon close icon-pre-text');
             cancelbutton.append('span').attr('class','label').text('Cancel');
 
         var warnings = body.selectAll('div.warning-section')