diff: add -Naur create patch file example (#6484)

pages/common/diff.md

@@ -9,20 +9,24 @@
 
 - Compare files, ignoring white spaces:
 
-`diff -w {{old_file}} {{new_file}}`
+`diff --ignore-all-space {{old_file}} {{new_file}}`
 
 - Compare files, showing the differences side by side:
 
-`diff -y {{old_file}} {{new_file}}`
+`diff --side-by-side {{old_file}} {{new_file}}`
 
 - Compare files, showing the differences in unified format (as used by `git diff`):
 
-`diff -u {{old_file}} {{new_file}}`
+`diff --unified {{old_file}} {{new_file}}`
 
 - Compare directories recursively (shows names for differing files/directories as well as changes made to files):
 
-`diff -r {{old_directory}} {{new_directory}}`
+`diff --recursive {{old_directory}} {{new_directory}}`
 
 - Compare directories, only showing the names of files that differ:
 
-`diff -rq {{old_directory}} {{new_directory}}`
+`diff --recursive --brief {{old_directory}} {{new_directory}}`
+
+- Create a patch file for Git from the differences of two text files, treating nonexistent files as empty:
+
+`diff --text --unified --new-file {{old_file}} {{new_file}} > {{diff.patch}}`