ROOT macro to create MVD simulation geomteries
Imported commits by Phillip Klaus over from https://git.cbm.gsi.de/mvd/simulation-geometry Branches in this repo contain other versions of the MVD simulation geometry.
Squash his 11 commits to 3 which introduce the v17, v20a and v20c creations macros.
Move to correct folder and update README file to record move.
Include author and licence holder for Phillip Klaus and the Institut für Kernphysik, Goethe-Universität Frankfurt