Support PowerShell v5 environment

[altrive]

Currently there is no definition for PowerShell v5 environment. (should be .NET 4.6?)
and it handled as ".NETFramework,Version=v4.0.0.0".
Therefore it failed to load assemblies that support net45\net50 environment only.

https://github.com/altrive/PSNuGet/blob/master/PSNuGet/Scripts/Use-NuGetPackage.ps1#L55-L61

Example packages

Use-NuGetPackage RazorEngine -Version 4.1.5-beta1 -Verbose
Use-NuGetPackage Microsoft.AspNet.Razor -Version 4.0.0-beta3 -Verbose

[beatcracker]

It should be .NET 4.5 (source): You’ll need .NET Framework 4.5 installed to run WMF 5.0

Quick-n-dirty patch that worked for me:

switch -Wildcard ($PSVersionTable.PSVersion){
    '3.0' { $frameworkName = '.NETFramework,Version=v4.0' }
    '4.0' { $frameworkName = '.NETFramework,Version=v4.5' }
    '5.0*' { $frameworkName = '.NETFramework,Version=v4.5' }
    default{ $frameworkName = [NuGet.VersionUtility]::DefaultTargetFramework }
}

[beatcracker]

On second thought, maybe it's better to check what CLR version is PS using ($PSVersionTable.CLRVersion) and load assemblies compatible with it. This will allow module to function correctly if PS was forced to use higher CLR version that it was supposed to use (i.e. How can I run PowerShell with the .NET 4 runtime?)