fix(select2theme): avoid incorrect padding between grouped and single

Author: dimirc

src/select.css

@@ -24,6 +24,10 @@
     border-color: #D44950;
 }
 
+.select2-result-single {
+  padding-left: 0;
+}
+
 /* Selectize theme */
 
 /* Helper class to show styles when focus */

src/select2/choices.tpl.html

@@ -1,7 +1,7 @@
 <ul class="ui-select-choices ui-select-choices-content select2-results">
   <li class="ui-select-choices-group" ng-class="{'select2-result-with-children': $select.isGrouped}">
     <div ng-show="$select.isGrouped" class="ui-select-choices-group-label select2-result-label">{{$group}}</div>
-    <ul class="select2-result-sub">
+    <ul ng-class="{'select2-result-sub': $select.isGrouped, 'select2-result-single': !$select.isGrouped}">
       <li class="ui-select-choices-row" ng-class="{'select2-highlighted': $select.isActive(this)}">
         <div class="select2-result-label ui-select-choices-row-inner"></div>
       </li>