Documentation import fixes (#11070)

* Move asyncdispatch imports below introduction

* Move nre imports below documentation

lib/impure/nre.nim

@@ -6,18 +6,6 @@
 #    distribution, for details about the copyright.
 #
 
-
-from pcre import nil
-import nre/private/util
-import tables
-from strutils import `%`
-from math import ceil
-import options
-from unicode import runeLenAt
-
-export options
-
-
 ## What is NRE?
 ## ============
 ##
@@ -67,6 +55,15 @@ runnableExamples:
     let matchBounds = firstVowel.get().captureBounds[-1]
     doAssert matchBounds.a == 1
 
+from pcre import nil
+import nre/private/util
+import tables
+from strutils import `%`
+from math import ceil
+import options
+from unicode import runeLenAt
+
+export options
 
 # Type definitions {{{
 type

lib/pure/asyncdispatch.nim

@@ -7,23 +7,6 @@
 #    distribution, for details about the copyright.
 #
 
-include "system/inclrtl"
-
-import os, tables, strutils, times, heapqueue, lists, options, asyncstreams
-import options, math
-import asyncfutures except callSoon
-
-import nativesockets, net, deques
-
-export Port, SocketFlag
-export asyncfutures except callSoon
-export asyncstreams
-
-#{.injectStmt: newGcInvariant().}
-
-## AsyncDispatch
-## *************
-##
 ## This module implements asynchronous IO. This includes a dispatcher,
 ## a ``Future`` type implementation, and an ``async`` macro which allows
 ## asynchronous code to be written in a synchronous style with the ``await``
@@ -162,6 +145,20 @@ export asyncstreams
 ##
 ## * The effect system (``raises: []``) does not work with async procedures.
 
+include "system/inclrtl"
+
+import os, tables, strutils, times, heapqueue, lists, options, asyncstreams
+import options, math
+import asyncfutures except callSoon
+
+import nativesockets, net, deques
+
+export Port, SocketFlag
+export asyncfutures except callSoon
+export asyncstreams
+
+#{.injectStmt: newGcInvariant().}
+
 # TODO: Check if yielded future is nil and throw a more meaningful exception
 
 type