All calculators are now classes, for sake of uniformity
Cosmetic changes
Renamed the calculator classes in CamelCase
Cleaned up the implementation of the Curve and removed useless cruft
Cached the interpolation operation in the Curve
Removed the multicurve functionality since it was not used
Added a test to make sure that Curves are pickeable
Cosmetic changes and added a comment
Fixed indentation
Improved a docstring
Cleanup (PEP8 and removed useless one-line functions)
More cleanup and removed the microfunction _loss_ratios
Removed with_unique_ordinates
Other improvements to the Curve
Other cosmetic changes
More cleanups of the risklib
Merged from master
Merge pull request #24 from gem/1081937

Cleanup of risklib, in particular of the calculators and curve.Curve