Improved error messagees, implemented delete ciphers, attachments and account, implemented two factor recovery.

Known missing:
 - import ciphers, create ciphers types other than login and card, update ciphers
 - clear and put device_tokens
 - Equivalent domains
 - Organizations

src/db/models/attachment.rs

@@ -63,6 +63,10 @@ impl Attachment {
     }
 
     pub fn delete(self, conn: &DbConn) -> bool {
+        use util;
+
+        util::delete_file(&self.get_file_path());
+
         match diesel::delete(attachments::table.filter(
             attachments::id.eq(self.id)))
             .execute(&**conn) {