To install using Typings:
$ npm install -g typings # If you haven't got it already
$ typings install --save --global github:jdnichollsc/Phaser-Kinetic-Scrolling-Plugin/typescript # You should really specify a commit version i.e. github:jdnichollsc/Phaser-Kinetic-Scrolling-Plugin/typescript#GIT_COMMIT_HASH_HERE
Note that Typings is officially depracated - a more modern approach would be to create a PR onto https://github.com/DefinitelyTyped/DefinitelyTyped so that you can use the now standard npm install @types/phaser-kinectic-scrolling-plugin command.