Enable migrated accounts with email-as-login to authenticate themselves.

src/App/Validation/Login.purs

@@ -34,7 +34,7 @@ login_parser :: G.Parser LoginParsingError String
 login_parser = do
   input <- G.current_input
   _ <- (alpha <|> digit) G.<:> \_ -> CannotParse
-  _ <- A.many (alpha <|> digit <|> G.char ' ' <|> G.char '_' <|> G.char '\'' <|> G.char '-')
+  _ <- A.many (alpha <|> digit <|> G.char ' ' <|> G.char '_' <|> G.char '\'' <|> G.char '-' <|> G.char '@' <|> G.char '.' <|> G.char '+')
   _ <- SomeParsers.eof G.<:> \_ -> CannotEntirelyParse
   let last_char_correct = G.parse_last_char input.string (alpha <|> digit)
   pos <- G.current_position