Add dotNet core support

Author: appleneko2001

tak2flac.Test/tak2flac.Test.csproj

@@ -1,15 +1,11 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netcoreapp3.0</TargetFramework>
+    <TargetFramework>netcoreapp3.1</TargetFramework>
 
     <IsPackable>false</IsPackable>
   </PropertyGroup>
 
-  <ItemGroup>
-    <None Remove="data\マイペースでいきましょう.tak" />
-  </ItemGroup>
-
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.5.0" />
     <PackageReference Include="MSTest.TestAdapter" Version="2.1.0" />
@@ -18,7 +14,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <ProjectReference Include="..\tak2flac\tak2flac.csproj" />
+    <ProjectReference Include="..\tak2flac\tak2flac.Core.csproj" />
   </ItemGroup>
 
   <ItemGroup>

tak2flac/Properties/AssemblyInfo.cs

@@ -10,7 +10,7 @@
 [assembly: AssemblyConfiguration("")]
 [assembly: AssemblyCompany("")]
 [assembly: AssemblyProduct("tak2flac")]
-[assembly: AssemblyCopyright("Copyright ©  2020")]
+[assembly: AssemblyCopyright("github@appleneko2001")]
 [assembly: AssemblyTrademark("")]
 [assembly: AssemblyCulture("")]
 

tak2flac/tak2flac.Core.csproj

@@ -0,0 +1,32 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <RootNamespace>tak2flac</RootNamespace>
+    <AssemblyName>tak2flac</AssemblyName>
+    <TargetFramework>netcoreapp3.1</TargetFramework>
+  </PropertyGroup>
+
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
+    <PlatformTarget>AnyCPU</PlatformTarget>
+    <Prefer32Bit>true</Prefer32Bit>
+    <DefineConstants>DEBUG;TRACE</DefineConstants>
+  </PropertyGroup>
+
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|AnyCPU'">
+    <Prefer32Bit>true</Prefer32Bit>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Newtonsoft.Json" Version="12.0.3" />
+    <Reference Include="System"/>   
+    <Reference Include="Microsoft.CSharp"/>
+    <Reference Include="System.Data"/>
+    <Reference Include="System.Xml"/>
+  </ItemGroup>
+
+  <ItemGroup>
+    <None Include="app.config"/>
+    <None Include="packages.config"/>
+    <Compile Remove="Properties\AssemblyInfo.cs"/>
+  </ItemGroup>
+</Project>