fixed a memory leak

see #1580

app/scripts/presenters/entry-presenter.js

@@ -17,6 +17,10 @@ EntryPresenter.prototype = {
         }
         return this;
     },
+    reset() {
+        this.entry = null;
+        this.group = null;
+    },
     get id() {
         return this.entry ? this.entry.id : this.group.id;
     },

app/scripts/views/list-view.js

@@ -112,6 +112,7 @@ class ListView extends View {
             presenter.present(this.items[0]);
             const itemTemplate = this.getItemTemplate();
             const itemsHtml = itemTemplate(presenter, DefaultTemplateOptions);
+            presenter.reset();
 
             const html = itemsTemplate(
                 { itemsHtml, columns: this.tableColumns },
@@ -186,6 +187,7 @@ class ListView extends View {
             itemsHtml += itemTemplate(presenter, DefaultTemplateOptions);
             renderedIndices.push(ix);
         }
+        presenter.reset();
 
         const tempEl = document.createElement('div');
         tempEl.innerHTML = itemsHtml;
@@ -221,6 +223,7 @@ class ListView extends View {
 
         this.presenter.present(item);
         const itemHtml = itemTemplate(this.presenter, DefaultTemplateOptions);
+        this.presenter.reset();
 
         const tempEl = document.createElement('div');
         tempEl.innerHTML = itemHtml;