WebUI: make API locale independet

Sizes are now given in bytes.
Dates are Unix timestamps and converted to ISO 8601 in the web UI.
Numbers are not converted to strings.
-1 is returned for undefined values.

Some keys have been splitted:

Torrent list (json/torrents)
 * num_seeds: Torrent seeds connected to
 * num_complete: Torrent seeds in the swarm
 * num_leechs: Torrent leechers connected to
 * num_incomplete: Torrent leechers in the swarm

Torrent generic properties (propertiesGeneral/hash)
 * total_uploaded: Total data uploaded
 * total_uploaded_session: Total data uploaded this session
 * total_downloaded: Total data dowloaded
 * total_downloaded_session: Total data downloaded this session
 * time_elapsed: Torrent elapsed time
 * seeding_time: Torrent elapsed time while complete
 * nb_connections: Torrent connection count
 * nb_connections_limit: Torrent connection count limit

Global transfer info (json/transferInfo)
 * dl_info_speed: Global downalod rate
 * dl_info_data: Data downloaded this session
 * up_info_speed: Global upload rate
 * up_info_data: Data uploaded this session

Closes #1524.

src/webui/www/private/index.html

@@ -18,6 +18,7 @@
 	<![endif]-->
 	<script type="text/javascript" src="scripts/mocha-yc.js"></script>
 	<script type="text/javascript" src="scripts/mocha-init.js"></script>
+	<script type="text/javascript" src="scripts/misc.js"></script>
 	<script type="text/javascript" src="scripts/progressbar.js"></script>
 	<script type="text/javascript" src="scripts/dynamicTable.js" charset="utf-8"></script>
 	<script type="text/javascript" src="scripts/client.js" charset="utf-8"></script>