Fix style in Request Life Cycle section.

Co-authored-by: pancho horrillo <pedrofelipe.horrillo@bbva.com>

docs/source/theory/request_life_cycle.rst

@@ -8,6 +8,7 @@ answered by the `User HTTP Interface`.
 
 
 1. request
+----------
 
 The user makes a request to the `User HTTP Interface`.
 
@@ -17,6 +18,7 @@ answered by the `User HTTP Interface`.
   with other requests that could be running concurrently.
 
 2. spawn
+--------
 
 ``kapow`` spawns the executable specified as entrypoint in the matching
 route.
@@ -31,6 +33,7 @@ answered by the `User HTTP Interface`.
 - ``KAPOW_CONTROLAPI_URL``: With the URL of the `Control HTTP Interface`
 
 3. ``kapow set /response/body banana``
+--------------------------------------
 
 During the lifetime of the shell, the request and response resources are
 available via these commands:
@@ -39,16 +42,17 @@ answered by the `User HTTP Interface`.
 
 - ``kapow set /response/...``
 
-   - These commands use the aforementioned environment variables to read data from
-   the user request and to write the response.
-
-   - They accept data either as arguments or from stdin.
+These commands use the aforementioned environment variables to read data
+from the user request and to write the response.  They accept data
+either as arguments or from ``stdin``.
 
 4. exit
+-------
 
 The shell dies.
 
 5. response
+-----------
 
 ``kapow`` finalizes the original request.