Reset arguments on 'kiss help' function

This removes the previous arguments when calling kiss help so that
they are not listed as extensions. This is not a big issue, but
someone can type

    kiss help please

and 'please' would be shown as an available extension.

Signed-off-by: Dylan Araps <dylan.araps@gmail.com>

kiss

@@ -1347,6 +1347,8 @@ args() {
 
             log "Installed extensions (kiss-* in \$PATH)"
 
+            set --
+
             for path in $(KISS_PATH=$PATH pkg_find kiss-\* all); do
                 set -- "${path#*/kiss-}" "$@"
                 max=$((${#1} > max ? ${#1} : max))