add core project and application layer

SIX/SIX/SIX.ApplicationLayer/SIX.ApplicationLayer.csproj

+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>netcoreapp2.2</TargetFramework>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <Folder Include="Student\" />
+  </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\SIX.Core\SIX.Core.csproj" />
+  </ItemGroup>
+</Project>

SIX/SIX/SIX.ApplicationLayer/Student/IStudentService.cs

+using System;
+using System.Collections.Generic;
+
+namespace SIX.ApplicationLayer.Student
+{
+    public interface IStudentService
+    {
+        List<SIX.Core.Student.Student> GetAll();
+    }
+}

SIX/SIX/SIX.ApplicationLayer/Student/StudentService.cs

+using System;
+using System.Collections.Generic;
+using SIX.Core.Student;
+
+namespace SIX.ApplicationLayer.Student
+{
+    public class StudentService : IStudentService
+    {
+        public List<Core.Student.Student> GetAll()
+        {
+            return new List<Core.Student.Student>
+            {
+                new Core.Student.Student { NIM = "001", Name = "A" },
+                new Core.Student.Student { NIM = "002", Name = "B" },
+                new Core.Student.Student { NIM = "003", Name = "C" },
+                new Core.Student.Student { NIM = "004", Name = "D" }
+            };
+        }
+    }
+}

SIX/SIX/SIX.Core/SIX.Core.csproj

+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>netcoreapp2.2</TargetFramework>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <Compile Remove="Class1.cs" />
+  </ItemGroup>
+  <ItemGroup>
+    <Folder Include="Student\" />
+  </ItemGroup>
+</Project>

SIX/SIX/SIX.Core/Student/Student.cs

+using System;
+namespace SIX.Core.Student
+{
+    public class Student
+    {
+        public string Name { get; set; }
+        public string NIM { get; set; }
+    }
+}

SIX/SIX/SIX.Infrastructure/SIX.Infrastructure.csproj

+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>netcoreapp2.2</TargetFramework>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\SIX.Core\SIX.Core.csproj" />
+  </ItemGroup>
+</Project>

SIX/SIX/SIX.sln

+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio 15
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SIX.Core", "SIX.Core\SIX.Core.csproj", "{C865F8A4-CB57-4F70-8E26-0717449BCE60}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SIX.ApplicationLayer", "SIX.ApplicationLayer\SIX.ApplicationLayer.csproj", "{06168B2D-FB8B-47DD-A8B9-301A507279BF}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SIX.Infrastructure", "SIX.Infrastructure\SIX.Infrastructure.csproj", "{C591D340-97B2-46CF-92E8-A1E717E83600}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{C865F8A4-CB57-4F70-8E26-0717449BCE60}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{C865F8A4-CB57-4F70-8E26-0717449BCE60}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{C865F8A4-CB57-4F70-8E26-0717449BCE60}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{C865F8A4-CB57-4F70-8E26-0717449BCE60}.Release|Any CPU.Build.0 = Release|Any CPU
+		{06168B2D-FB8B-47DD-A8B9-301A507279BF}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{06168B2D-FB8B-47DD-A8B9-301A507279BF}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{06168B2D-FB8B-47DD-A8B9-301A507279BF}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{06168B2D-FB8B-47DD-A8B9-301A507279BF}.Release|Any CPU.Build.0 = Release|Any CPU
+		{C591D340-97B2-46CF-92E8-A1E717E83600}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{C591D340-97B2-46CF-92E8-A1E717E83600}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{C591D340-97B2-46CF-92E8-A1E717E83600}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{C591D340-97B2-46CF-92E8-A1E717E83600}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+EndGlobal