Refs #10622.  Added algorithm to load HFIR PDD.

* new file:   Framework/DataHandling/inc/MantidDataHandling/LoadHFIRPDD.h
* new file:   Framework/DataHandling/src/LoadHFIRPDD.cpp
* new file:   Framework/DataHandling/test/LoadHFIRPDDTest.h
Refs #10622.  Modified CMake file.