Null safety and pedantic analysis

[stargazing-dino]

Hi!

Thought I would move this over to null-safety. I had to remove the example lib and recreate it using flutter create again because there was some hefty manual changes that it was asking me to do otherwise. I also added analysis options so that things could be more consistent.

Let me know if this is unwelcome or if you want any changes. I tested example on android, iOS and web and all worked ok.

Thanks!

[knezzz]

Oh great! Thanks :D
I will merge this, but Ill probably release new version over the weekend :)

[stargazing-dino]

I'm glad it was helpful :) Sorry too ! I forgot to update changelog. If you do get a new version soon, I'd also add that it's updated to null safety there