update changelog (and add generation stuff for future)

Rakefile

@@ -1,4 +1,5 @@
 require "bundler/gem_tasks"
+require "github_changelog_generator/task"
 
 task :default => :test
 
@@ -6,3 +7,8 @@ mock = ENV['FOG_MOCK'] || 'true'
 task :test do
   sh("export FOG_MOCK=#{mock} && bundle exec shindont")
 end
+
+GitHubChangelogGenerator::RakeTask.new :changelog do |config|
+  config.user = 'fog'
+  config.project = 'fog-aws'
+end