[PATCH v2] Improve --assume-unchanged in the git update-index man page

This version 2 patch squashes in Junio's comments ($gmane/260915) and tidies up the commit message. Previous series at $gmane/260901.

In $gmane/260837 the --assume-unchanged flag was reported as buggy because of a misunderstanding about what it is being promised.

This clarifies the current situation, rather than change the code as proposed by Duy in $gmane/260865.

Philip Oakley (1):
  doc: make clear --assume-unchanged's user contract

 Documentation/git-update-index.txt | 18 ++++++++----------
 1 file changed, 8 insertions(+), 10 deletions(-)