Revert "Update move-with-hist.ps1: add script description"

This reverts commit 801eea4d59.

move-with-hist.ps1

@@ -1,8 +1,4 @@
-# NOTE: for internal use only
-# This script moves a source file to a target file in repository,
-# but ensures its history is preserved, i.e. commits, author date.
-
-param (
+param (
     [Parameter(Mandatory=$true)][string]$source,
     [Parameter(Mandatory=$true)][string]$target
 )