Add various deleted flags to entities | Add active to subscriptions | Add DeleteUser && DeleteChannel endpoints [skip-tests]

flutter/lib/pages/account/account.dart

@@ -503,7 +503,7 @@ class _AccountRootPageState extends State<AccountRootPage> {
   }
 
   void _deleteAccount() async {
-    Toaster.info("Not Implemented", "Account Upgrading will be implemented in a later version"); // TODO
+    // TODO
   }
 
   void _changeUsername() async {

flutter/lib/pages/send/send.dart

@@ -151,7 +151,7 @@ class _SendRootPageState extends State<SendRootPage> {
             controller: _senderName,
             decoration: const InputDecoration(
               border: OutlineInputBorder(),
-              labelText: 'SenderName',
+              labelText: 'Sender',
             ),
           ),
         ),