Base: Add missing options to sort man page

Base/usr/share/man/man1/sort.md

@@ -12,6 +12,14 @@ $ sort [INPUT]
 
 Sort each lines of INPUT (or standard input). A quick sort algorithm is used.
 
+## Options
+
+* `-k keydef`, `--key-field keydef`: The field to sort by
+* `-u`, `--unique`: Don't emit duplicate lines
+* `-n`, `--numeric`: Treat the key field as a number
+* `-t char`, `--sep char`: The separator to split fields by
+* `-r`, `--reverse`: Sort in reverse order
+
 ## Examples
 
 ```sh