Add a clear button to the tag / branch filter input fields; simplify

the jQuery code a bit.

src/IDF/templates/idf/source/mtn/tree.html

@@ -51,15 +51,16 @@
 <a href="{$url}"><img style="vertical-align: text-bottom;" src="{media '/idf/img/package-grey.png'}" alt="{trans 'Archive'}" align="bottom" /></a> <a href="{$url}">{trans 'Download this version'}</a> {trans 'or'}
 <kbd>mtn clone {$project.getSourceAccessUrl($user, $commit)}</kbd> <a href="{url 'IDF_Views_Source::help', array($project.shortname)}"><img style="vertical-align: text-bottom;" src="{media '/idf/img/help.png'}" alt="{trans 'Help'}" /></a>
 </p>
-
-
 {/block}
 {block context}
 <div class="expander">
 <div class="gradient"></div>
 <h1>
   {trans 'Branches'}
-  <input type="text" rel="branch-list" class="filter-list"  title="{trans 'filter branches'}" />
+  <div class="input-with-delete">
+    <input type="text" rel="branch-list" class="filter-list"  title="{trans 'filter branches'}" />
+    <span></span>
+  </div>
 </h1>
 <ul id="branch-list">
 {foreach $branches as $selector => $branch}
@@ -72,7 +73,10 @@
 {if $tags}
 <h1>
   {trans 'Tags'}
-  <input type="text" rel="tag-list" class="filter-list"  title="{trans 'filter tags'}" />
+  <div class="input-with-delete">
+    <input type="text" rel="tag-list" class="filter-list"  title="{trans 'filter tags'}" />
+    <span></span>
+  </div>
 </h1>
 <ul id="tag-list">
 {foreach $tags as $selector => $tag}
@@ -85,3 +89,4 @@
 {/if}
 </div>
 {/block}
+