Rename interfact name.  Refs #6555.
Rename poweder diffraction gui name.  Refs #6555.
Some minor changes.  Refs #6555.

1. Set the default value of FilterBadPulse and PreserveEvents to True;
2. Clean up some error message output;
Clean output messages.  Refs #6556.
Add input 'Output File Prefix'.  Refs #6555.