Dmitry Malyshev / ctools

So far any exception occuring during the construction of the ctools were not catched. This is corrected now.

All likelihood ctools now derive from the ctlikelihood base class. This avoids code duplication and provides all likelihood tools with a uniform interface.

(still need to remove some debug statements later)

…served events in ctlike.

…erLM logger constructor interface (now takes a pointer instead of a reference).