Added back button interceptor

[feduke-nukem]

Closes #178
Closes #114
Closes #86

As I myself have faced this problem, I added BackButtonInterceptor package, so if it's declared no userInteractions, there will be no route popping

[RogerBrusamarello]

@nslogx please could you aprove this PR?

[hellohejinyu]

@feduke-nukem Dude, you deleted your fork and my code crashed. Because I'm directly referencing your branch code😭

[feduke-nukem]

@feduke-nukem Dude, you deleted your fork and my code crashed. Because I'm directly referencing your branch code😭

Sorry, I was doing some cleanup and didn't intend to break anyone's code. This PR is almost a year old, so I believe the code owner should take a look at it, at least. From my side, I will try to restore this repo and branch asap.

[hellohejinyu]

Haha thanks, but I've re-forked one from your codebase. Considering that other developers may have used your code, you can indeed restore it.😊

[feduke-nukem]

Haha thanks, but I've re-forked one from your codebase. Considering that other developers may have used your code, you can indeed restore it.😊

You could check the branch now.

Additionally, I would like to mention that I have been working on my own implementation of an overlay-based dialog system in Flutter. You might want to take a look link

My main goal is to provide a flexible system, so I would be happy to receive feedback from anyone.

[hellohejinyu]

You could check the branch now.

Additionally, I would like to mention that I have been working on my own implementation of an overlay-based dialog system in Flutter. You might want to take a look.: link

My main goal is to provide a flexible system, so I would be happy to receive feedback from anyone.

Wow, flutter_easy_dialogs is really cool, I think I can use it in our app in the future.