Started the implementation of Rwp cost function.  Refs #7476.
Checkpointing work.  Refs #7476.
Checkpointing work.  Refs #7476.

Implemented the Hessian matrix and Derivative vector.  It works with
non-Levenberg-Marquadt minimzers.  The result looks fine.
Modifed to be inherited.  Refs #7476.

Modify CostFuncLeastSquare such that CostFuncRwp can inherit from it.
Changed inheritance.  Refs #7476.

Made CostFuncRwp inherit from CostFuncLeastSquares other than
CostFuncFitting.
Added some unit tests related.  Refs #7476.
Added class variable for cost function factor.  Refs #7476.
Merge branch 'master' into feature/7476_new_costfun_rwp
Removed 1 debug output.  Refs #7476.
Added 1 more row in Fit's output table.  Refs #7476.
Removed the 4th line in output table.  Refs #7476.
Commented out debug output.  Refs #7476.
Fixed unit test.  Refs #7476.
Cleaned the code.  Refs #7476.
Cleaned the code.  Refs #7476.
Merge remote branch 'origin/feature/7476_new_costfun_rwp'