Merge pull request #5205 from grpc/release-0_13

examples/ruby/greeter_client.rb

examples/ruby/route_guide/route_guide_client.rb

package.json

templates/package.json.template

test/distrib/ruby/Gemfile

test/distrib/ruby/distribtest.gemspec

test/distrib/ruby/distribtest.rb

test/distrib/ruby/run_distrib_test.sh

tools/dockerfile/distribtest/ruby_centos6_x64/Dockerfile

tools/dockerfile/distribtest/ruby_centos7_x64/Dockerfile

tools/dockerfile/distribtest/ruby_fedora20_x64/Dockerfile

tools/dockerfile/distribtest/ruby_fedora21_x64/Dockerfile

tools/dockerfile/distribtest/ruby_fedora22_x64/Dockerfile

tools/dockerfile/distribtest/ruby_fedora23_x64/Dockerfile

tools/dockerfile/distribtest/ruby_jessie_x64/Dockerfile

tools/dockerfile/distribtest/ruby_jessie_x86/Dockerfile

tools/dockerfile/distribtest/ruby_opensuse_x64/Dockerfile

tools/dockerfile/distribtest/ruby_ubuntu1204_x64/Dockerfile

tools/dockerfile/distribtest/ruby_ubuntu1404_x64/Dockerfile

tools/dockerfile/distribtest/ruby_ubuntu1504_x64/Dockerfile