Fix multiple file uploading.

Item ID was set statically to uuid(). When two file were uploaded, both
got the same ID, and only one ItemView was shown, though both files were
uploaded. Multiple file uploading now works at least in recent Firefox
and Chromium, but not in Opera.

fileshack/static/fileshack/js/fileshack.js

@@ -89,7 +89,6 @@ var FileShack = new Class({
         });
 
         //window.setInterval(function() { this_.update() }, this.options.updateInterval);
-        window.uuid = uuid();
         //this.update();
 
         if ($('watchbtn')) {

fileshack/static/fileshack/js/models.js

@@ -63,7 +63,7 @@ var Item = new Class({
     Extends: Model,
 
     defaults: {
-	id: uuid(),
+	id: -1,
 	type: 'complete', // 'pending', 'unfinished', 'stale', 'complete'.
         name: '',
 	url: '',
@@ -75,6 +75,11 @@ var Item = new Class({
         modified: new Date()
     },
 
+    initialize: function(attributes) {
+	this.parent(attributes);
+	this.id = uuid();
+    },
+
     update: function(json) {
 	if (this.type == 'pending')
 	    ; // Do nothing.