Some refactoring of the risk calculators [skip hazardlib]
Some refactoring of the risk calculators [skip hazardlib]


Former-commit-id: bd9972c9c5056c4300896d92d4fa176442ac9773 [formerly cace15d139c41e5345e12cefb578aaa0baca1046] [formerly cace15d139c41e5345e12cefb578aaa0baca1046 [formerly 0259736f4ba4bfb6b8892454de503687f76f780d]]
Former-commit-id: 14174403a5d2afbec52b7a843cd3d26f1f8f71b9
Former-commit-id: 7de774200e5a5698faefb0901e37560d010c0fac
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine