copy language files to output of main project

fixes translation of UI fields that are not plugin-specific

Author: JohnTheGr8

Flow.Launcher/Flow.Launcher.csproj

@@ -54,6 +54,14 @@
     <Compile Include="..\SolutionAssemblyInfo.cs" Link="Properties\SolutionAssemblyInfo.cs" />
   </ItemGroup>
 
+  <ItemGroup>
+    <Content Include="Languages\*.xaml">
+      <Generator>MSBuild:Compile</Generator>
+      <SubType>Designer</SubType>
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Content>
+  </ItemGroup>
+
   <ItemGroup>
     <PackageReference Include="InputSimulator" Version="1.0.4" />
     <PackageReference Include="JetBrains.Annotations" Version="2019.1.3" />