Refs #9531. Added ComainCreator for FunctionDomain1DSpectrum.
Refs #9531. Added SeqDomainSpectrumCreator with test.
Refs #9531. Setting fit values in FunctionDomain1DSpectrumCreator.
Refs #9531. Added fitting tests.
Refs #9531. Adjusted Fit to make tests work.
Refs #9531. Added test function for SeqDomainSpectrumCreator.
Refs #9531. Added demonstration algorithm.

The algorithms fits the test function to the provided workspace data. Useful for profiling "real world data" with appropriate dimensions (data and parameters).
Refs #9531. Mapping fit weights in CostFuncFitting.

Instead of calling the virtual function getWeights each time fit weights are accessed in LeastSquaresCostFunc, they are mapped once before the calculations.
Refs #9531. Further reduced number of virtual function calls.

Followed Roman's suggestion to make getFitWeights() virtual and remove getWeight as well as calSqrtW from CostFuncLeastSquares.
Refs #9531. Added documentation to domain creators.
Refs #9531. Added check for SeqDomainSpectrumCreator in Fit.
Refs #9531. Cleaned up SeqDomanSpectrumCreatorTest.
Refs #9531. Removed test function and demonstration algorithm.

This is already in the unit tests now and SeqDomainTestFunction and SeqDomainDemonstration don't do anything useful.
Merge branch 'feature/9531_SpectrumSeqDomainCreator' into develop