Add changelog link to gemspec for rubygems.org (#31)

Author: tilo

after_commit_everywhere.gemspec

@@ -28,6 +28,8 @@ Gem::Specification.new do |spec|
   spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
   spec.require_paths = ["lib"]
 
+  spec.metadata["changelog_uri"] = "https://github.com/Envek/after_commit_everywhere/blob/master/CHANGELOG.md"
+
   spec.add_dependency "activerecord", ">= 4.2"
   spec.add_dependency "activesupport"
   spec.add_development_dependency "appraisal"