Merge pull request #97 from javierhe/master

Added LinkStateSet & LinkStateDebugSet MO
Correcting variable names in some tests.
Merge pull request #98 from mnjuhn/master

Correcting variable names/comments in demand tests.
Moving PIF MO into measurements sub package.
Ensuring unit tests are conisistent with regards to trapping exceptions and throwing assertion error.
Merge pull request #99 from mnjuhn/master

Moving PIF MO and unit test consistency.