Feature: Add Explorer option "Launch folder windows in a separate process"

[AnthonyMastrean]

This is a pretty important setting for surviving Explorer.exe crashes.

Seems to be located in the "advanced" registry key, as SeparateProcess (with values off: 0 and on: 1)

PS> get-item HKCU:\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced


    Hive: HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer


Name                           Property
----                           --------
Advanced                       Start_SearchFiles       : 2
                               ServerAdminUI           : 0
                               Hidden                  : 2
                               ShowCompColor           : 1
                               HideFileExt             : 1
                               DontPrettyPath          : 0
                               ShowInfoTip             : 1
                               HideIcons               : 0
                               MapNetDrvBtn            : 0
                               WebView                 : 1
                               Filter                  : 0
                               ShowSuperHidden         : 0
                               SeparateProcess         : 1
                               AutoCheckSelect         : 0
                               IconsOnly               : 0
                               ShowTypeOverlay         : 1
                               ShowStatusBar           : 1
                               ListviewAlphaSelect     : 1
                               ListviewShadow          : 1
                               TaskbarAnimations       : 1
                               StoreAppsOnTaskbar      : 1
                               StartMenuInit           : 13
                               TaskbarStateLastRun     : {159, 227, 84, 90...}
                               ReindexedProfile        : 1
                               DisablePreviewDesktop   : 1
                               DontUsePowerShellOnWinX : 0
                               SnapAssist              : 1
                               NavPaneShowAllFolders   : 1
                               TaskbarSizeMove         : 1
                               TaskbarSmallIcons       : 0
                               TaskbarBadges           : 0
                               ShowTaskViewButton      : 1