Merge remote-tracking branch 'origin/feature/6761_zooming_on_pick_tab'
Merge remote-tracking branch 'origin/feature/3692_param_string_org'
Merge remote branch 'origin/feature/6465_purge_libgit2'
Implement powder reduction GUI.  Refs #6555 and #6556.

1. Add Interface "Powder Reduction"
2. Enable "Powder Reduction" to support NOM, PG3 and VULCAN
3. Add all the python and UI files required by GUI
Remove used and rename UI files.  Refs #6555.

1. Deleted unused sample_setup;
2. Rename van_setup to adv_setup;
Rename van setup to adv setup.  Refs #6555.

1. Rename van_setup to adv_setup
2. Delete sample_setup
Renamed VanadiumSetup to AdvancedSetup.  Refs #6555.
Fix a bug caused by renaming.  Refs #6555.
Correct name of advanced setup UI.  Refs #6555.
Modify GUI setup.  Refs #6555.
Modify GUI setup.  Refs #6556.
Improve GUI.  Refs #6555.
Improve GUI.  Refs #6556.
Improve event filtering GUI.  Refs #6556.

Improvements include:
1. Add event handling to disable/enable widgets if different filtering
approach is selected;
2. Clean the GUI.
3. Add filter info as a helping message.
Improve powder data reduction GUI.  Refs #6555.

Improvements include:
1. Move preserve-events and file extension to advanced setup tab;
2. Clean GUI;
3. Add helping infomation;
4. Add tool tip to each widget.
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.