move Duration docs below common/ next to Scheduler

akka-docs/common/index.rst

@@ -5,3 +5,4 @@ Common utilities
    :maxdepth: 2
 
    scheduler
+   duration

akka-docs/general/index.rst

@@ -10,5 +10,4 @@ General
    configuration
    event-handler
    issue-tracking
-   util
    licenses

akka-docs/general/util.rst

@@ -1,49 +0,0 @@
-#########
-Utilities
-#########
-
-.. sidebar:: Contents
-
-   .. contents:: :local:
-
-This section of the manual describes miscellaneous utilities which are provided
-by Akka and used in multiple places.
-
-.. _Duration:
-
-Duration
-========
-
-Durations are used throughout the Akka library, wherefore this concept is
-represented by a special data type, :class:`Duration`. Values of this type may
-represent infinite (:obj:`Duration.Inf`, :obj:`Duration.MinusInf`) or finite
-durations, where the latter are constructable using a mini-DSL:
-
-.. code-block:: scala
-
-   import akka.util.duration._   // notice the small d
-
-   val fivesec = 5.seconds
-   val threemillis = 3.millis
-   val diff = fivesec - threemillis
-   assert (diff < fivesec)
-
-.. note::
-
-   You may leave out the dot if the expression is clearly delimited (e.g.
-   within parentheses or in an argument list), but it is recommended to use it
-   if the time unit is the last token on a line, otherwise semi-colon inference
-   might go wrong, depending on what starts the next line.
-
-Java provides less syntactic sugar, so you have to spell out the operations as
-method calls instead:
-
-.. code-block:: java
-
-   final Duration fivesec = Duration.create(5, "seconds");
-   final Duration threemillis = Duration.parse("3 millis");
-   final Duration diff = fivesec.minus(threemillis);
-   assert (diff.lt(fivesec));
-   assert (Duration.Zero().lt(Duration.Inf()));
-
-