Update close vars

* Remove dupe hover color var (again, it's not necessary to have it's
own var here since we're controlling it via `opacity`)
* Add to customizer

_includes/nav-customize.html

@@ -28,6 +28,7 @@
     <li><a href="#variables-pagination">Pagination</a></li>
     <li><a href="#variables-labels">Labels</a></li>
     <li><a href="#variables-tooltips-popovers">Tooltips and popovers</a></li>
+    <li><a href="#variables-close">Close button</a></li>
     <li><a href="#variables-other">Other</a></li>
   </ul>
 </li>

customize.html

@@ -1191,9 +1191,16 @@ lead: Customize Bootstrap's components, LESS variables, and jQuery plugins to ge
           <p class="help-block">Popover outer arrow color</p>
         </div>
       </div>
+
+      <h2 id="variables-close">Close button</h2>
+      <label>@close-color</label>
+      <input type="text" placeholder="#000">
+      <label>@close-text-shadow</label>
+      <input type="text" placeholder="0 1px 0 #fff">
+
       <h2 id="variables-other">Other</h2>
       <div class="row">
-      <div class="col-lg-6">
+        <div class="col-lg-6">
           <label>@hr-border</label>
           <input type="text" placeholder="@gray-lighter">
           <p class="help-block">Horizontal line color</p>

less/close.less

@@ -14,7 +14,7 @@
 
   &:hover,
   &:focus {
-    color: @close-hover-color;
+    color: @close-color;
     text-decoration: none;
     cursor: pointer;
     .opacity(.5);

less/variables.less

@@ -422,8 +422,7 @@
 // Close
 // ------------------------
 @close-color:                 #000;
-@close-hover-color:           #000;
-@close-text-shadow:           0 1px 0 rgba(255,255,255,1);
+@close-text-shadow:           0 1px 0 #fff;
 
 
 // Code