pacdiff: add page (#8474)

pages/linux/pacdiff.md

@@ -0,0 +1,28 @@
+# pacdiff
+
+> Maintenance utility for `.pacorig`, `.pacnew` and `.pacsave` files created by `pacman`.
+> More information: <https://man.archlinux.org/man/pacdiff>.
+
+- Review files that need maintenance in interactive mode:
+
+`pacdiff`
+
+- Use sudo and sudoedit to remove and merge files:
+
+`pacdiff --sudo`
+
+- Review files needing maintenance, creating `.bak`ups of the original if you `(O)verwrite`:
+
+`pacdiff --sudo --backup`
+
+- Use a specific editor to view and merge configuration files (default is `vim -d`):
+
+`DIFFPROG={{editor}} pacdiff`
+
+- Scan for configuration files with `locate` instead of using pacman database:
+
+`pacdiff --locate`
+
+- Display help:
+
+`pacdiff --help`