Tweak indentation of class definition with non-hanging object

Indent non-hanging `object` instead of aligning with their preceding
`class` token. Previously:

class c =
object
  method m = 1
end

Now:

class c =
  object
    method m = 1
  end

which agrees with default ocp-indent and seems to be the more modern
usage. Also indent `initialize` clauses correctly. (ocaml#239)

indent-test.ml

@@ -852,11 +852,38 @@ let () =
       >>= fun () -> step2)
 
 class c (a : b) =
-object
+  object
+    inherit d
+    method m = 1
+  end
+
+class c (a : b) =
+  object(self)
+    inherit d
+    method m = 1
+  end
+
+class c (a : b) = object
   inherit d
   method m = 1
 end
 
+class c (a : b) = object(self)
+  inherit d
+  method m = 1
+end
+
+class type restricted_point_type =
+  object
+    method get_x : int
+    method bump : unit
+  end
+
+class type restricted_point_type = object
+  method get_x : int
+  method bump : unit
+end
+
 let f = {
     a = 1;
   }

tuareg.el

@@ -2221,15 +2221,16 @@ Return values can be
    ;; An important role of this first condition is to call smie-indent-virtual
    ;; so that we get called back to compute the (virtual) indentation of
    ;; "object", thus making sure we get called back to apply the second rule.
-   ((and (member token '("inherit" "val" "method" "constraint"))
+   ((and (member token '("inherit" "val" "method" "constraint" "initializer"))
          (smie-rule-parent-p "object"))
     (save-excursion
       (forward-word 1)
       (goto-char (nth 1 (smie-backward-sexp 'halfsexp)))
       (let ((col (smie-indent-virtual)))
         `(column . ,(+ tuareg-default-indent col)))))
    ;; For "class foo = object(type)...end", align object...end with class.
-   ((and (equal token "object") (smie-rule-parent-p "class"))
+   ((and (equal token "object") (smie-rule-parent-p "class")
+         (not (smie-rule-bolp)))
     (smie-rule-parent))))
 
 (defun tuareg-smie--if-then-hack (token)