fixes for 1.0.5

## [1.0.5]

- adds support for the new PointerPanZoom*Event family on Listenable that overrides the mouse Signal (mouse wheel) on desktop OS.
  Basically, currently on desktop builds, everytime a mouse wheel event is triggered, a PointerPanZoomEvent is dispatched on the Listenable.
  Check [MyButton] in [SimpleInteractionsMain] demo, for an example of how to use it.
- add Generic Type [T] support to addChild
- updated some samples for the API.

fix missing pivotY testing for transformations.

fix changelog

Merge pull request roipeker#20 from IsmailAlamKhan/null-safety

Migrated the examples to null-safety

## [0.9.10]

- start porting to null-safety in the other branch.
- fix a bug with `GText` layout.
- update dependencies in *examples/*
- removed `flutter_icons`.

Merge pull request roipeker#10 from roipeker/dev

update 0.9.7