Renamed two risk calculator for consistency with the renaming in risklib
Fixed direct calls to x_values and y_values
Removed range_clip, Curve, and Vulnerability functions, since they were all ported to risklib
Merge branch 'master' of https://github.com/gem/oq-engine into 1081937
Merged from master
Merged from master
Merge pull request #991 from gem/1081937

Changes associated to the bug #1081937