add angel3_framework, vania and fennec

[insinfo]

add angel3_framework https://pub.dev/packages/angel3_framework
vania https://pub.dev/packages/vania
fennec https://pub.dev/packages/fennec

The angel3_framework is an extremely robust framework with many useful features for developing robust web applications. I've been using it for years since the early days of Dart. I've lost count of how many applications I've developed with it on the backend and AngularDart on the frontend over the years. It's worth testing. Vania and Fennec are very young frameworks that still need to be battle-tested.

[SirusCodes]

Thanks for the suggestions, I currently don't have much time to implement these but you are welcome to raise a PR.