Documentation tweaks

docs/plugins.rst

@@ -116,9 +116,6 @@ This hook is called when a new SQLite database connection is created. You can
 use it to `register custom SQL functions <https://docs.python.org/2/library/sqlite3.html#sqlite3.Connection.create_function>`_,
 aggregates and collations. For example:
 
-
-Example implementation:
-
 .. code-block:: python
 
     import click
@@ -134,4 +131,5 @@ This registers a SQL function called ``hello`` which takes a single
 argument and can be called like this::
 
 .. code-block:: sql
+
     select hello("world"); -- "Hello, world!"