cc-2188: Download action for all media file.

Download action were added in two placese.

1. Playlist Builder. jjmenu now showing 'Download'.
2. Calendar-> Show Content. Click on the file, you will see
Downlaod menu.

Limitation:

File name is set to original file name.
On the ticket it said, file format should be like
"show_name-12012011-2130.mp3". However, in my opinion,
this is only possible, if a user downloads it from
calender->show content. We know what the show names and etc,
but, if the user downloads it from Playlist Builder, we cannot
retrive such information. To be consistent in both area, I just
set the file name to original file name. This can be easily
modified in the future.

airtime_mvc/application/views/scripts/schedule/show-content-dialog.phtml

@@ -11,7 +11,7 @@
     </tr>
 <?php $i=0; ?>
 <?php foreach($this->showContent as $row): ?>
-    <tr class="<?php if($i&1){echo "even";}else{echo "odd";}?>">
+    <tr id="au_<?php echo $row["file_id"] ?>" class="<?php if($i&1){echo "even";}else{echo "odd";}?>">
         <td><?php echo $row["starts"] ?></td>
         <td><?php echo $row["track_title"] ?></td>
         <td><?php echo $row["artist_name"] ?></td>