ADD Improvements to the release script

Add a new mode for the Code Complete and the preparation for the next version working.
This assumes that the current version in package.json and create-rpm.sh is e.g. "0.1.0". Thus, the line will change "0.1.0" for "0.1.0-next", i.e. the post-branching steeping.

But, what about the pre-branching stepping in which package.json/create-rpm.sh containt "0.1.0-next"? The sed line seems not be valid in this case...