feat: Trash (#1082)

* wip: trash

* Enable restoration of deleted documents

* update Trash icon

* Add endpoint to trigger garbage collection

* fix: account for drafts

* fix: Archived documents should be deletable

* fix: Missing delete cascade

* bump: upgrade rich-markdown-editor

app/models/Document.js

@@ -1,5 +1,6 @@
 // @flow
 import { action, set, computed } from 'mobx';
+import addDays from 'date-fns/add_days';
 import invariant from 'invariant';
 import { client } from 'utils/ApiClient';
 import parseTitle from 'shared/utils/parseTitle';
@@ -76,6 +77,15 @@ export default class Document extends BaseModel {
     return !this.publishedAt;
   }
 
+  @computed
+  get permanentlyDeletedAt(): ?string {
+    if (!this.deletedAt) {
+      return;
+    }
+
+    return addDays(new Date(this.deletedAt), 30).toString();
+  }
+
   @action
   share = async () => {
     const res = await client.post('/shares.create', { documentId: this.id });