Work-in-progress on sanitizing unknown handling in ensembles
Merge branch 'master' of ssh://alice.wu-wien.ac.at/usr/local/src/git-repo/nsf
Adding a test showing the yet to solve unknown-handling issue in info ensembles
- improve safety of macro arguments
Merge branch 'master' of ssh://alice.wu-wien.ac.at/usr/local/src/git-repo/nsf
- make compilation clean again
nsf.c:
- implement a new approach to error reporting in ensembles:
  instead of trying to find the "right" place to report the best "error",
  compute the longest valid ensemble prefix from all the stack frames.
- extend regression test
nx.tcl:
- simplify the info ensembles on nx::Object or nx::Class significantly,
  by making use if ensemble-next.
- delete "info unknown", since this is not called.