Fix typo (vuejs#1392)

morrislaptop · Akryum · commit 9332f244566f · 2018-05-29T16:41:40.000+02:00
diff --git a/docs/cli.md b/docs/cli.md
@@ -45,7 +45,7 @@ start and open the vue-cli ui
 
 Options:
 
-  -p, --port <port>  Port used for the UI server (by default search for awailable port)
+  -p, --port <port>  Port used for the UI server (by default search for available port)
   -h, --help         output usage information
 ```
 
