fix some small things in HTTP

akka-docs-dev/rst/scala/http/index-routing.rst

@@ -13,6 +13,7 @@ HTTP Routing
    exception-handling
    path-matchers
    marshalling
+   custom-directives
    directives/alphabetically
    directives/by-trait
 

akka-docs-dev/rst/scala/http/server.rst

@@ -4,7 +4,7 @@ Server API
 ==========
 
 The Akka HTTP server is an embedded, stream-based, fully asynchronous, low-overhead
-HTTP/1.1 server implemented on top of `Akka Streams`_. (todo: fix link)
+HTTP/1.1 server implemented on top of :ref:`streams-scala`.
 
 It sports the following features:
 
@@ -16,7 +16,6 @@ It sports the following features:
 
 .. _HTTP persistent connections: http://en.wikipedia.org/wiki/HTTP_persistent_connection
 .. _HTTP pipelining: http://en.wikipedia.org/wiki/HTTP_pipelining
-.. _Akka streams: http://akka.io/docs/
 
 
 Design Philosophy
@@ -154,4 +153,4 @@ field of an HTTP message:
 SSL Support
 -----------
 
-(todo)
+(todo)

akka-docs-dev/rst/scala/stream-index.rst

@@ -1,3 +1,5 @@
+.. _streams-scala:
+
 Streams
 =======