Code cleanup

[satano]

I have forked this repo, because I am investigating possibilities fo migrating on-premise TFS to Azure DevOps. There are hundreds of warnings in the solution. I consider a warning as a potential error so I always try to have minimum of them (preferably zero). Basically, the only warning I keep visible in projects I work on is Obsolete waning. All other warnings are either fixed, or accepted and so hidden by configuration so they do not show up. I identified these problems in the code. If you are interested, I can fix most of them – in several PRs.

Mixed .NET

MigrationTools.Clients.TfsObjectModel projects is in .NET Framework 4.7 because it references libraries which are available only for this framework. Other projects are some in .NET Framework 4.7, some in .NET 8 together with .NET Standard 2.0. This makes mess and warnings that some ligraries are restored in different framework than they should be. Is there a reson for .NET 8? I think, that in this case all projects can be just in .NET Framework 4.7 and everything will be OK.

Old/mixed package references

There are multiple warnings about references with high severity vulnerabities and some packages which are used (indirectely) in various versions.

Nullability warnings

There is a lot of warnings related to nullable references. I would either turn of nullable references, or fix the warnings.

Various code analysis varnings

For example never used fileds, async without await, overriding obsoletes members, broken XML comments and some more.

Unused and duplicated usings

I would just use Remove and sort usings feature of Visual Studio to fix theese.

[MrHinsh]

We accept PR's 👍

If there a lot of changes, please keep them as concise as possible

[MrHinsh]

Loved the first one @satano !