first pass
Merge branch 'master' into refactor-risk-calculators
classical qa tests pass
classical bcr qa tests pass
scenario qa tests pass
improved doc
all the qa tests pass
risk export tests pass
added a new export tests for event based e2d
Merge branch 'master' of https://github.com/gem/oq-engine into refactor-risk-calculators
fix risk event based when gets an hc as input
added check for loss fractions
updated old calculator tests
improved doc
replaced namedtuples with standard classes
Merge pull request #1164 from matley/refactor-risk-calculators

Refactoring of risk calculators