Drop support for outdated frameworks (net461, net472 and netstandard2.0)

[Jericho]

I started thinking about dropping support for frameworks that have reached end-of-life (or will reach it soon or have been replaced by a framework version that will be supported longer-term) a while ago and I intend to implement the following changes in the next major release:

• Drop net461 and net472 and replace them with net48
• Drop netstandard2.0 and replace it with netstandard2.1
• Add support for net6.0

[groege]

• et461 and net472 and replace them with net48
• Drop netstandard2.0 and replace it with netstandard2.1
• Add support for net6.0

Please do not! Many projects including ours rely on 4.8 and cannot be migrated...
I'm also pretty sure we are not the only ones - there is so much legacy code that has still to be maintained and kept up to date to ensure IT security (we also have contracts to update libraries when possible)

--> it will take us at least 5 years to migrate (if even possible) to later net versions

[Jericho]

Many projects including ours rely on 4.8 and cannot be migrated...

I indicated that I would replace net461 and net472 with net48 so I don't understand your objection.