Add a header and/or footer to the vacation message

Fixes #1961

SoObjects/SOGo/SOGoTextTemplateFile.h

@@ -0,0 +1,40 @@
+/* SOGoTextTemplateFile.h - this file is part of SOGo
+ *
+ * Copyright (C) 2016 Inverse inc.
+ *
+ * This file is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This file is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifndef SOGOTEXTTEMPLATEFILE_H
+#define SOGOTEXTTEMPLATEFILE_H
+
+@class SOGoUser;
+
+@interface SOGoTextTemplateFile : NSObject
+{
+  NSString *_textTemplate;
+}
+
++ (id) textTemplateFromFile: (NSString *) file;
+
+- (id) initFromFile: (NSString *) file
+       withEncoding: (NSStringEncoding) enc;
+
+- (NSString *) textForUser: (SOGoUser *) user;
+
+@end
+
+#endif /* SOGOTEXTTEMPLATEFILE_H */