Migrate to new CS Project format

migrate.ps1

function Extract-ProjectReferences ($projectFile) {
    [regex]::matches((Get-Content $projectFile), '<ProjectReference Include=\"([^"]*)\"') | ForEach-Object { $_.Groups[1].Value }
}

function Extract-NuGetReferences ($nugetFile) {
    [regex]::matches((Get-Content $nugetFile), '<package id=\"([^"]*)\" version=\"([^"]*)\"') | ForEach-Object { @{ Name = $_.Groups[1].Value; Version = $_.Groups[2].Value } } 
}

function Get-UpgradedProjectFile ($projectFile) {
    $nugetReferences = Extract-NuGetReferences  ($projectFile.DirectoryName + "\packages.config")
    $nugetReferencesSection = $nugetReferences | ForEach-Object { '    <PackageReference Include="' + $_.Name + '" Version="' + $_.Version + '" />' } | Out-String
    $projectReferences = Extract-ProjectReferences $projectFile
    $projectReferenceSection = $projectReferences | ForEach-Object { '    <ProjectReference Include="' + $_ + '" />' } | Out-String
    return '<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>net471</TargetFramework>
    <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
  </PropertyGroup>
  <ItemGroup>
' + $projectReferenceSection + '
  </ItemGroup>
  <ItemGroup>
' + $nugetReferencesSection + '
  </ItemGroup>
</Project>'
}

function Upgrade-AllProjects {
    $projectFiles = get-childitem "*.csproj" -Recurse
    foreach ($projectFile in $projectFiles) {
        Write-Host "Generating new project file for $projectFile"
        $newProjectFile = Get-UpgradedProjectFile $projectFile
        Rename-Item $projectFile ($projectfile.FullName + ".old") -Force
        Set-Content -Path $projectFile -Value $newProjectFile
    }
}