(chocolateyGH-458) Conditional compilation symbols for .NET version

.NET doesn't have compiler conditionals for the different
versions of the .NET Frameworks, so it's not possible out of the
box to target different functionality based on the .NET versions.
Add a property group in a targets file based on
http://stackoverflow.com/a/29001688/18475 and ensure that both
chocolatey and chocolatey.console VS projects use those targets
files.

src/chocolatey.console/chocolatey.console.csproj

@@ -121,6 +121,9 @@
     </None>
     <None Include="packages.config" />
     <None Include="targets\Microsoft.Application.targets" />
+    <None Include="targets\NET.Compile.targets">
+      <SubType>Designer</SubType>
+    </None>
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\chocolatey.resources\chocolatey.resources.csproj">
@@ -139,6 +142,7 @@
   </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <Import Project=".\targets\Microsoft.Application.targets" />
+  <Import Project=".\targets\NET.Compile.targets" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it.
        Other similar extension points exist, see Microsoft.Common.targets.
   <Target Name="BeforeBuild">

src/chocolatey.console/targets/NET.Compile.targets

@@ -0,0 +1,19 @@
+<!--Based on http://stackoverflow.com/a/29001688/18475 -->
+<!--
+******************************************************************
+Defines the Compile time symbols
+Modelled from https://msdn.microsoft.com/en-us/library/ms171464.aspx
+*********************************************************************
+-->
+
+
+<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+    <PropertyGroup>
+        <DefineConstants Condition="$([System.Version]::Parse('$(TargetFrameworkVersion.Substring(1))').CompareTo($([System.Version]::Parse('4.5.2')))) &gt;= 0">$(DefineConstants);NETFX_452</DefineConstants>
+        <DefineConstants Condition="$([System.Version]::Parse('$(TargetFrameworkVersion.Substring(1))').CompareTo($([System.Version]::Parse('4.5.1')))) &gt;= 0">$(DefineConstants);NETFX_451</DefineConstants>
+        <DefineConstants Condition="$([System.Version]::Parse('$(TargetFrameworkVersion.Substring(1))').CompareTo($([System.Version]::Parse('4.5'))))   &gt;= 0">$(DefineConstants);NETFX_45</DefineConstants>
+        <DefineConstants Condition="$([System.Version]::Parse('$(TargetFrameworkVersion.Substring(1))').CompareTo($([System.Version]::Parse('4.0'))))   &gt;= 0">$(DefineConstants);NETFX_40</DefineConstants>
+        <DefineConstants Condition="$([System.Version]::Parse('$(TargetFrameworkVersion.Substring(1))').CompareTo($([System.Version]::Parse('3.5'))))   &gt;= 0">$(DefineConstants);NETFX_35</DefineConstants>
+        <DefineConstants Condition="$([System.Version]::Parse('$(TargetFrameworkVersion.Substring(1))').CompareTo($([System.Version]::Parse('3.0'))))   &gt;= 0">$(DefineConstants);NETFX_30</DefineConstants>
+    </PropertyGroup>
+</Project>

src/chocolatey/chocolatey.csproj

@@ -273,6 +273,7 @@
     </EmbeddedResource>
     <None Include="packages.config" />
     <None Include="targets\Microsoft.Application.targets" />
+    <None Include="targets\NET.Compile.targets" />
   </ItemGroup>
   <ItemGroup>
     <None Include="..\..\docs\logo\chocolatey.ico">
@@ -291,6 +292,7 @@
   </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <Import Project=".\targets\Microsoft.Application.targets" />
+  <Import Project=".\targets\NET.Compile.targets" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it.
        Other similar extension points exist, see Microsoft.Common.targets.
   <Target Name="BeforeBuild">

src/chocolatey/targets/NET.Compile.targets

@@ -0,0 +1,19 @@
+<!--Based on http://stackoverflow.com/a/29001688/18475 -->
+<!--
+******************************************************************
+Defines the Compile time symbols
+Modelled from https://msdn.microsoft.com/en-us/library/ms171464.aspx
+*********************************************************************
+-->
+
+
+<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+    <PropertyGroup>
+        <DefineConstants Condition="$([System.Version]::Parse('$(TargetFrameworkVersion.Substring(1))').CompareTo($([System.Version]::Parse('4.5.2')))) &gt;= 0">$(DefineConstants);NETFX_452</DefineConstants>
+        <DefineConstants Condition="$([System.Version]::Parse('$(TargetFrameworkVersion.Substring(1))').CompareTo($([System.Version]::Parse('4.5.1')))) &gt;= 0">$(DefineConstants);NETFX_451</DefineConstants>
+        <DefineConstants Condition="$([System.Version]::Parse('$(TargetFrameworkVersion.Substring(1))').CompareTo($([System.Version]::Parse('4.5'))))   &gt;= 0">$(DefineConstants);NETFX_45</DefineConstants>
+        <DefineConstants Condition="$([System.Version]::Parse('$(TargetFrameworkVersion.Substring(1))').CompareTo($([System.Version]::Parse('4.0'))))   &gt;= 0">$(DefineConstants);NETFX_40</DefineConstants>
+        <DefineConstants Condition="$([System.Version]::Parse('$(TargetFrameworkVersion.Substring(1))').CompareTo($([System.Version]::Parse('3.5'))))   &gt;= 0">$(DefineConstants);NETFX_35</DefineConstants>
+        <DefineConstants Condition="$([System.Version]::Parse('$(TargetFrameworkVersion.Substring(1))').CompareTo($([System.Version]::Parse('3.0'))))   &gt;= 0">$(DefineConstants);NETFX_30</DefineConstants>
+    </PropertyGroup>
+</Project>