Updates to new synchronization module

Author: pitr-ch

Rakefile

@@ -1,7 +1,7 @@
 #!/usr/bin/env rake
 
-required 'concurrent/version'
-required 'concurrent/native_extensions'
+require 'concurrent/version'
+require 'concurrent/native_extensions'
 
 ## load the two gemspec files
 CORE_GEMSPEC = Gem::Specification.load('concurrent-ruby.gemspec')

lib/concurrent/edge/future.rb

@@ -78,7 +78,7 @@ def post_on(executor, *args, &job)
     extend FutureShortcuts
     include FutureShortcuts
 
-    class Event < Concurrent::SynchronizedObject
+    class Event < Synchronization::Object
       extend FutureShortcuts
 
       # @api private
@@ -576,7 +576,7 @@ def pr_async_callback_on_completion(success, value, reason, executor, callback)
     # TODO modularize blocked_by and notify blocked
 
     # @abstract
-    class AbstractPromise < Concurrent::SynchronizedObject
+    class AbstractPromise < Synchronization::Object
       # @api private
       def initialize(*args, &block)
         super(&nil)