* crypto: implement automagic decryption when so requested

(mainly by adding some smartness to various part_foreach functions, adding
  mu_msg_(get|set)_auto_decrypt to mark a message for auto-decryption)

lib/mu-msg.c

@@ -84,7 +84,8 @@ msg_new (void)
 }
 
 MuMsg*
-mu_msg_new_from_file (const char *path, const char *mdir, GError **err)
+mu_msg_new_from_file (const char *path, const char *mdir,
+		      GError **err)
 {
 	MuMsg *self;
 	MuMsgFile *msgfile;
@@ -169,6 +170,26 @@ mu_msg_unref (MuMsg *self)
 }
 
 
+void
+mu_msg_set_auto_decrypt (MuMsg *msg, gboolean autodecrypt)
+{
+	g_return_if_fail (msg);
+	mu_msg_load_msg_file (msg, NULL);
+	msg->_file->_auto_decrypt = autodecrypt;
+}
+
+
+gboolean
+mu_msg_get_auto_decrypt (MuMsg *msg)
+{
+	g_return_val_if_fail (msg, FALSE);
+	if (!msg->_file)
+		return FALSE;
+	return msg->_file->_auto_decrypt;
+}
+
+
+
 /* use this instead of mu_msg_get_path so we don't get into infinite
  * regress...*/
 static const char*
@@ -377,8 +398,6 @@ mu_msg_get_timestamp (MuMsg *self)
 }
 
 
-
-
 const char*
 mu_msg_get_path (MuMsg *self)
 {