Update changelog, and fix exchanger in edge

Author: pitr-ch

CHANGELOG.md

@@ -4,17 +4,23 @@ concurrent-ruby:
 
 * [Promises](http://ruby-concurrency.github.io/concurrent-ruby/Concurrent/Promises.html)
   are moved from `concurrent-ruby-edge` to `concurrent-ruby`
+* Add support for TruffleRuby
+  * (#734) Fix Array/Hash/Set construction broken on TruffleRuby
+  * AtomicReference fixed    
+* CI stabilization
+* remove sharp dependency edge -> core
+* remove warnings
+* documentation updates
+* Exchanger is no longer documented as edge since it was already available in 
+  `concurrent-ruby`
 * (#644) Fix Map#each and #each_pair not returning enumerator outside of MRI
 * (#659) Edge promises fail during error handling
 * (#741) Raise on recursive Delay#value call
 * (#727) #717 fix global IO executor on JRuby
 * (#740) Drop support for CRuby 1.9, JRuby 1.7, Rubinius.
 * (#737) Move AtomicMarkableReference out of Edge
 * (#708) Prefer platform specific memory barriers 
-* Add support for TruffleRuby
-  * (#734) Fix Array/Hash/Set construction broken on TruffleRuby    
 * (#735) Fix wrong expected exception in channel spec assertion
-* CI stabilization
 * (#729) Allow executor option in `Promise#then`
 * (#725) fix timeout check to use timeout_interval
 * (#719) update engine detection
@@ -27,9 +33,6 @@ concurrent-ruby:
   v3.7.0
 * (#665) Initialize the monitor for new subarrays on Rubinius
 * (#661) Fix error handling in edge promises
-* remove sharp dependency edge -> core
-* remove warnings
-* documentation updates
 
 concurrent-ruby-edge:
 

lib-edge/concurrent-edge.rb

@@ -3,7 +3,6 @@
 require 'concurrent/actor'
 require 'concurrent/agent'
 require 'concurrent/channel'
-require 'concurrent/exchanger'
 require 'concurrent/lazy_register'
 
 require 'concurrent/edge/lock_free_linked_set'

lib/concurrent/exchanger.rb

@@ -24,7 +24,6 @@ module Concurrent
   #   will remain correct.
   #
   #   @see http://docs.oracle.com/javase/7/docs/api/java/util/concurrent/Exchanger.html java.util.concurrent.Exchanger
-  #   @!macro warn.edge
   #   @example
   #
   #     exchanger = Concurrent::Exchanger.new