[TS] Proper TypeScript/JavaScript Package

[raphael-goetz]

The TypeScript Package is lacking some needed features. Adjust the build process to include:

• JS files. This would make it posible to easily build or use this package for the ActionSDK in the future (its planed to do this sdk in js)
• Provide a index.d.ts to resolve the issue with long import paths.

[raphael-goetz]

I really need this asap @Taucher2003