Make Nerdbank.GitVersioning applicable to more projects

In particular since this package is made up purely of build features, we apply to *all* projects.

Author: AArnott

src/Nerdbank.GitVersioning.NuGet/Nerdbank.GitVersioning.NuGet.nuproj

@@ -52,7 +52,9 @@
     <Content Include="..\NerdBank.GitVersioning\version.schema.json">
       <Link>tools\version.schema.json</Link>
     </Content>
+    <Content Include="build\dotnet\Nerdbank.GitVersioning.targets" />
     <Content Include="build\NerdBank.GitVersioning.targets" />
+    <Content Include="build\portable-net+win+wpa+wp+sl+net-cf+netmf+MonoAndroid+MonoTouch+Xamarin.iOS\Nerdbank.GitVersioning.targets" />
     <Content Include="tools\Get-Version.ps1" />
     <Content Include="tools\Get-CommitId.ps1" />
     <Content Include="tools\Create-VersionFile.ps1" />

src/Nerdbank.GitVersioning.NuGet/build/dotnet/Nerdbank.GitVersioning.targets

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <Import Project="..\$(MSBuildThisFileName)$(MSBuildThisFileExtension)" />
+</Project>

src/Nerdbank.GitVersioning.NuGet/build/portable-net+win+wpa+wp+sl+net-cf+netmf+MonoAndroid+MonoTouch+Xamarin.iOS/Nerdbank.GitVersioning.targets

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <Import Project="..\$(MSBuildThisFileName)$(MSBuildThisFileExtension)" />
+</Project>