add permission view only

Signed-off-by: Marino Faggiana <marino@marinofaggiana.com>

iOSClient/NCGlobal.swift

@@ -272,6 +272,8 @@ class NCGlobal: NSObject {
     @objc let permissionDefaultFileRemoteShareNoSupportShareOption: Int     = 3
     @objc let permissionDefaultFolderRemoteShareNoSupportShareOption: Int   = 15
 
+    @objc let permissionViewOnly: Int               = 1
+
     // Filename Mask and Type
     //
     let keyFileNameMask                             = "fileNameMask"