Only write a CMTK version 2.4 registration if we have CMTK >=3.0 available
Note change in R package dependency (nat) in README
README polishing
Merge branch 'feature/nat'

* feature/nat:
  README polishing
  Note change in R package dependency (nat) in README
  Only write a CMTK version 2.4 registration if we have CMTK >=3.0 available
  R does not need to be interactive
  switch from AnalysisSuite to nat/nat.utils dependency