Export single modules of sdk

[LukasHirt]

Currently, we are exporting a whole sdk as one single export and then use it globally in the web app. This leads to a need of passing around the sdk context between different parts which haven't got the access to it. A perfect example of this is the store. This is a bit tedious and it would be great if we could import the required modules directly when needed.

[LukasHirt]

Another advantage we could get with this would be tree shaking. It would probably require a different approach to storing some of the values in helpers. Maybe in a window object? Thoughts @kulmann @fschade ?