fix warning around 'Properties\Settings.settings' in Visual Studio

Following warning is displayed in "Error List" windows in Visual Studio.

Severity	Code	Description	Project	File	Line	Suppression State
Warning		A custom tool 'SettingsSingleFileGenerator' is associated with file 'Properties\Settings.settings', but the output of the custom tool was not found in the project.  You may try re-running the custom tool by right-clicking on the file in the Solution Explorer and choosing Run Custom Tool.

Steps to Reproduce:

1. File -> New -> Project -> Visual C# -> Windows Forms App (.NET Framework)
2. And drop button1 to Fomr1 to generate Form1.resx.
3. copy App.config, Form1.* Program.cs Properties*.*
4. create CMakeLists.txt.
5. cmake -G "Visual Studio 15 2017 Win64"
6. double click *.sln file

CMakeLists.txt :

cmake_minimum_required(VERSION 3.8)

project(WindowsFormsApp1 VERSION 0.1.0 LANGUAGES CSharp)

include(CSharpUtilities)

add_executable(WindowsFormsApp1
    App.config
    Program.cs

    Form1.cs
    Form1.Designer.cs
    Form1.resx

    Properties/AssemblyInfo.cs
    Properties/Resources.Designer.cs
    Properties/Resources.resx
    Properties/Settings.Designer.cs
    Properties/Settings.settings
)
set_target_properties(WindowsFormsApp1 PROPERTIES
    WIN32_EXECUTABLE                    true
    VS_DOTNET_TARGET_FRAMEWORK_VERSION  "v4.6.2"
    VS_GLOBAL_ROOTNAMESPACE             "WindowsFormsApp1"
)
csharp_set_windows_forms_properties(
    Form1.cs
    Form1.Designer.cs
    Form1.resx
)
csharp_set_designer_cs_properties(
    Properties/AssemblyInfo.cs
    Properties/Resources.Designer.cs
    Properties/Resources.resx
    Properties/Settings.Designer.cs
    Properties/Settings.settings
)
set_property(TARGET WindowsFormsApp1 PROPERTY VS_DOTNET_REFERENCES
    System
    System.Data
    System.Drawing
    System.Windows.Forms
    System.Xml
)

Environment:

Windows 10 Pro version 1703 build 15063.674 Visual Studio 2017 Community Version 15.4.1 cmake-3.10.0-rc4-win64-x64.msi + Merge Requst !1449 (merged) (Original CMake can not generate C# project for Visual Studio japanease version.My Visual Studio is japanease version.)

Confirm the facts

.csproj file is different from Visual Studio. VS Settings.Designer.cs CMake Properties\Settings.Designer.cs

And warning disappeared when I revised LastGenOutput tag manually. Therefore, I think that this is a problem of CMake generator.

Fix and confirmation

I modified cmVisualStudio10TargetGenerator.cxx that generate LastGenOutput tag. And I generate C# project by this CMake(Merge request !1449 (merged) Applied), then warning disappeared.

Than you, and I'm sorry my poor English.