Bump vcap-staging

vcap-staging shortlog d4349d3f..93f6a1f0

Elisabeth Hendrickson and Matthew Kocher (2):
  Update gemspec
  Updating gemfile to reflect gemspec

Maria Shaldybina (3):
  Add run plugin script
  Revert "Use global bundler"
  Update bundler to 1.2.1 for staging

Matthew Kocher and Tim Labeeuw (1):
  Initial Ruby and Node buildpack support

Change-Id: I82c0af7f1cb358938bab041e6ef65531b6d884fb