patch 8.2.2822: MS-Windows: unnessarily loading libraries when unregistering

Problem:    MS-Windows: unnessarily loading libraries when unregistering OLE.
Solution:   Also skip loading libraries when invoked with "-unregister".  Run
            Vim for README.txt with user privileges.

nsis/README.txt

@@ -66,6 +66,9 @@ To build the installable .exe:
 
 Install NSIS if you didn't do that already.
 Also install UPX, if you want a compressed file.
+Download and include the ShellExecAsUser.dll Unicode version which can be
+sourced from: https://nsis.sourceforge.io/ShellExecAsUser_plug-in
+
 
 Unpack the images:
 	cd nsis

nsis/gvim.nsi

@@ -119,9 +119,9 @@ RequestExecutionLevel highest
 
 !define MUI_COMPONENTSPAGE_SMALLDESC
 !define MUI_LICENSEPAGE_CHECKBOX
-!define MUI_FINISHPAGE_RUN                 "$0\gvim.exe"
+!define MUI_FINISHPAGE_RUN
+!define MUI_FINISHPAGE_RUN_FUNCTION        LaunchApplication
 !define MUI_FINISHPAGE_RUN_TEXT            $(str_show_readme)
-!define MUI_FINISHPAGE_RUN_PARAMETERS      "-R $\"$0\README.txt$\""
 
 # This adds '\Vim' to the user choice automagically.  The actual value is
 # obtained below with CheckOldVim.
@@ -300,6 +300,11 @@ Function CheckOldVim
   Exch $0  # put $0 on top of stack, restore $0 to original value
 FunctionEnd
 
+Function LaunchApplication
+   SetOutPath $0
+   ShellExecAsUser::ShellExecAsUser "" "$0\gvim.exe" "-R $"$0\README.txt$""
+FunctionEnd
+
 ##########################################################
 Section "$(str_section_old_ver)" id_section_old_ver
 	SectionIn 1 2 3 RO