Add warning about .net 2.0 framework reached EOL

[wing328]

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Description of the PR

Add warning about .net 2.0 framework reached EOL

[jimschubert]

I'd like to do this a little differently. I'll open a PR later today for feedback. Basically, I'm thinking about adding an 'isDeprecated' boolean to CodegenConfig. This will allow us to inform users of deprecated generators much earlier than at generation time, and allows us to display a warning in a centralized place.

I may also consider a more robust "State" object for metadata about the generator.

[wing328]

Basically, I'm thinking about adding an 'isDeprecated' boolean to CodegenConfig. This will allow us to inform users of deprecated generators much earlier than at generation time, and allows us to display a warning in a centralized place.

Sure. Let's improve the depreciation notice bit by bit.