Very minor docs fixes (angular#339)

Author: Alex Memering

docs/2-retrieving-data-as-objects.md

@@ -35,7 +35,7 @@ There are three ways to create an object binding:
 
 1. Relative URL
 2. Absolute URL
-3. Reference or Query
+3. Reference
 
 ```ts
 // relative URL, uses the database url provided in bootstrap

docs/3-retrieving-data-as-lists.md

@@ -29,7 +29,7 @@ class AppComponent {
 
 Data is retrieved through the `af.database` service.
 
-There are three ways to create an object binding:
+There are four ways to create an object binding:
 
 1. Relative URL
 2. Absolute URL