Wrong versions added for System.* redirects

Description

When referencing Microsoft.CodeAnalysis.CSharp, assembly bindings get created for System.* with the wrong version.

Repro steps

Create a .NET 4.7.1 console or web application, convert to Paket. Use this as dependencies:

source https://api.nuget.org/v3/index.json
framework: net471
nuget Microsoft.CodeAnalysis.CSharp

This as references:

Microsoft.CodeAnalysis.CSharp

Run paket install --redirects

Expected behavior

app.config does not have redirects that are breaking at runtime.

Actual behavior

Among others, System.IO.Compression is redirected to version 4.1.2.0 (latest on nuget) while the project actually uses an installed version 4.2.0.0.

Known workarounds

Disable generating these redirects in paket.dependencies:

System.IO.Compression redirects: off
System.Xml.XPath.XDocument redirects: off
System.Linq redirects: off
System.Linq.Expressions redirects: off
System.Security.Cryptography.Algorithms redirects: off
System.Runtime redirects: off
System.Runtime.Extensions redirects: off
System.Runtime.InteropServices redirects: off
System.Security.Cryptography.Primitives redirects: off
System.Threading.Thread redirects: off

Start by reproducing the paket install --redirects command with the stated net471 dependencies and inspect the generated app.config. Trace how Paket selects versions for the listed System.* redirects. Done means redirects reference the versions actually used by the project and no longer break at runtime.