contact request: add list of blocked contacts.

In preferences add new tab for banned contact. The list contain
contact's bestID and button to perform unban.

Change-Id: I376f63420ec0573e47574a79923c798b50148a31
Reviewed-by: Anthony LĂ©onard <anthony.leonard@savoirfairelinux.com>
diff --git a/src/AccBannedContactsVC.h b/src/AccBannedContactsVC.h
new file mode 100644
index 0000000..5a646fc
--- /dev/null
+++ b/src/AccBannedContactsVC.h
@@ -0,0 +1,26 @@
+/*
+ *  Copyright (C) 2015-2017 Savoir-faire Linux Inc.
+ *  Author: Kateryna Kostiuk <kateryna.kostiuk@savoirfairelinux.com>
+ *
+ *  This program 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 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program 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; if not, write to the Free Software
+ *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA.
+ */
+
+#import <Cocoa/Cocoa.h>
+
+@interface AccBannedContactsVC : NSViewController
+
+@property (nonatomic) BOOL bannedListIsEmpty;
+
+@end