Adds rci::oncilla::NotImplementedError

Now all std::runtime_error that reports an unimplemented feature
reports rci::oncilla::NotImplementedError instead.

This would allow to catch such problem more easily in L2 and L3 levels.

Now messages have a pedantic message to explain how to report such
issues, and remind that it always better to be served by himself than
to wait for me or Arne to get the things done.