Use unordered_map instead of map
rev 342
Change some method and member names in IOHandler and BaseAnalysis
Forgot the hh in previous commit
Implement Iterator for HistoHandler

Adding c++11 unordered_map and fallback solution to map

Adding flags to control CMAKE
C++11_COMPAT: use c++11 (not default)
NA62_DEBUG : use -g
FULL_WARNING : use all the warning and error flags