Update README.md

JosAchterberg · web-flow · commit 20e1f8467624 · 2019-01-22T13:05:19.000+01:00
It's now possible to specify a post_type
diff --git a/README.md b/README.md
@@ -1,4 +1,4 @@
 # facetwp-wp-cli
 Run indexing of FacetWP via WP-CLI
 
-`wp facet index`
+`wp facet index [post_type]`
