Refs #9179.  Added a new file for usage example.
Refs #9719.  Added usage example for ExaminePowderDiffProfile.

And corrected some bugs in this algorithm.
Refs #9719.  Claimed SelectPowderDiffPeaks deprecated.

And edit its sphinx doc.
Fixed doc test. Refs #9719.
Merge branch 'feature/9719_more_usage_example' into develop