add spaces

docs/en_US/BuiltinAssessor.md

@@ -19,7 +19,6 @@ Note: Please follow the format when you write your `config.yml` file.
 
 <a name="MedianStop"></a>
 
-
 ![](https://placehold.it/15/1589F0/000000?text=+) `Median Stop Assessor`
 
 > Builtin Assessor Name: **Medianstop**

docs/en_US/assessors.rst

@@ -13,7 +13,7 @@ Here is an experimental result of MNIST after using 'Curvefitting' Assessor in '
 Like Tuners, users can either use built-in Assessors, or customize an Assessor on their own. Please refer to the following tutorials for detail:
 
 ..  toctree::
-    :maxdepth:2
+    :maxdepth: 2
 
     builtin_assessor
     Customized Assessors<CustomizeAssessor>