Added a progress hook for load() when using the options object (#143)

• Supports PixiJS v7
• Drops support for PixiJS v6.
• Drops support for legacy assets - now only v2 of the asset format is supported.

Fixes an issue with final keyframes (#129)

Skew fixes (#124, #125, #128)

Allows shape data file (.shapes.json or .shapes.txt) urls to include query strings.

• Fixed an error in tweening rotations (#119).
• Add support for Node's multiple entry points.

Updated PixiJS dependencies to 6.0.0-rc.

Further improvements to the asset specific type generation (npx pixi-animate-type-assets) by having the output be a namespace, so that you can have const foo: myAsset.lib.Foo;.

• Fix a typo in AnimateAsset preventing the passing in of the library to setup() (as far as Typescript was concerned).
• Improve generated type information for asset files.
• Fix issues with holes in legacy bundle and asset upgrades.
• Handle *.shapes.txt files when upgrading assets.

Fixed library definitions for Typescript.