Change package version to 3.1.1

Set version to 3.1.0

PropertyContainer.propertyProxy to propertyProxyUssClassName

Make LICENSE a markdown file

This should prevent GitHub from recognizing LICENSE.meta as a license file.

Polish description in package.json

Fix package name

It was "com.unity.example". It slipped, sorry.

Remove Rebinder mentions from Readme

Update README and package.json