Process a md5 on the uploaded file, and display it in the per file view.

- The uploader can check that the uploaded file is correct
- The downloader can check his download too

src/IDF/templates/idf/downloads/view.html

@@ -5,6 +5,8 @@
 <div class="download-file">
 {if $deprecated}<p class="smaller">{blocktrans}<strong>Attention!</strong> This file is marked as deprecated, download it only if you are sure you need this specific version.{/blocktrans}</p>{/if}
 <a href="{url 'IDF_Views_Download::download', array($project.shortname, $file.file)}">{$file}</a> - {$file.filesize|size}
+<br />
+<span class="helptext">{trans 'md5:'} {$file.md5}</span>
 </div>
 {if $file.changelog}
 <h2 class="changes">{trans 'Changes'}</h2>