Update image_optim dependency 0.10.2 -> 0.11.1

Changes can be seen at:

  toy/image_optim@f1e5034...7664059

Change-Id: I1f6ff0059f5f075791c4d9edfb0a338deb45bd4d
Reviewed-on: http://gerrit.causes.com/35728
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>

Author: lencioni

overcommit.gemspec

@@ -29,5 +29,5 @@ Gem::Specification.new do |s|
   s.add_dependency             'wopen3'
 
   s.add_development_dependency 'rspec', '2.14.1'
-  s.add_development_dependency 'image_optim', '0.10.2'
+  s.add_development_dependency 'image_optim', '0.11.1'
 end