Adding bold to service doc to call up state and enabled.

library/system/service

@@ -37,8 +37,8 @@ options:
         description:
           - C(started)/C(stopped) are idempotent actions that will not run
             commands unless necessary.  C(restarted) will always bounce the
-            service.  C(reloaded) will always reload. At least one of state
-            and enabled are required.
+            service.  C(reloaded) will always reload. B(At least one of state
+            and enabled are required.)
     sleep:
         required: false
         version_added: "1.3"
@@ -59,8 +59,8 @@ options:
         required: false
         choices: [ "yes", "no" ]
         description:
-        - Whether the service should start on boot. At least one of state and
-          enabled are required.
+        - Whether the service should start on boot. B(At least one of state and
+          enabled are required.)
 
     runlevel:
         required: false