Update README.markdown

Author: lazychaser

README.markdown

@@ -13,6 +13,8 @@ The package can be installed as Composer package, just include it into
     "required": {
         "kalnoy/nestedset": "dev-master"
     }
+    
+And then hit `composer update` in the terminal. That's it - you are ready to go next.
 
 ## Basic usage
 
@@ -294,4 +296,4 @@ When you create your table's schema and use `NestedSet::columns`, it creates for
 key for you, since nodes are connected by `parent_id` attribute. When you hard delete
 the node, all of descendants are cascaded.
 
-In case when DBMS doesn't support foreign keys, descendants are removed manually.
+In case when DBMS doesn't support foreign keys, descendants are removed manually.