Fixup file size warning

Add contentType-specific limits, switch to lazy-init iff we encounter an
oversized file, and restyle as a toast, factoring out a generic
ToastView along the way.

js/views/toast_view.js

@@ -0,0 +1,37 @@
+/* vim: ts=4:sw=4:expandtab
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+var Whisper = Whisper || {};
+
+(function () {
+    'use strict';
+    Whisper.ToastView = Backbone.View.extend({
+        className: 'toast',
+        initialize: function() {
+            Mustache.parse(this.template);
+            this.$el.hide();
+        },
+
+        close: function() {
+            this.$el.fadeOut(this.remove.bind(this));
+        },
+
+        render: function() {
+            this.$el.html(Mustache.render(this.template, this.model));
+            this.$el.appendTo($('body')).show();
+            setTimeout(this.close.bind(this), 2000);
+        }
+    });
+})();