move code and split this repo

[hohwille]

This repo (devon) is "historically grown" and IMHO not clearly sorted.
In devonfw we do have a clear separation of stacks that is not followed here.
IMHO the code of this repo should be harmonized and moved to devon4j or a new devon4j-xxx repo.
The documentation should also be entirely reworked. All stack specific documentation shall be in the according stacks. This repo here should IMHO in the end only contain cross cutting aspects such as e.g.:
https://github.com/devonfw/devon4j/wiki/architecture#key-principles