Merge pull request #1051 from larsbutler/sa-classical-haz-qa-test

Classical Hazard QA test, SA IMT case

[r=micheles] [f=1073591]
Merge pull request #1050 from larsbutler/optimize-haz-curve-insertion

Optimize hazard curve insertion

[r=matley] [f=1100332]
qa_tests/hazard/disagg/case_1/test:

Updated expected test values. Bear in the mind that this test is currently
just for stability; the results were not independently computed.
calcs/hazard/disaggregation/core:

Use the new `disaggregation_poissonian` calc function.
qa_tests/hazard/disagg/case_1:

Added a 'hazard' nose attribute to this test case.
qa_tests/hazard/disagg/case_1/test:

Added a custom XML test method which has slightly relaxed precision when
comparing probability values.

The reason for this change is that there seem to be very minor differences
in these values, depending on the platform and environment.