Add linting rules to the package

[md-weber]

In the Pull Request #8 we had minor fixed and it would be beneficial to add some linting rules. We have two paths that we can do here.

1. Add the Lint package 🚀
2. Add the rules for prefer const etc. 👍

If you have a strong preference please use the icon above on this issue so we can fix accordingly.

[Abhishek01039]

https://pub.dev/packages/pedantic
what do you think about this? @md-weber

[md-weber]

I like the pedantic package but it is pretty hard aligned to the Flutter Repository needs. As a bit more "developer" friendly I currently prefer the lint package.
https://pub.dev/packages/lint

[Abhishek01039]

Great!!
Please go ahead.