Modified Ruby Version in Step 9, and added Step 10 to remove 'pry-byebug' gem which depends on Ruby 2.0

Referencing #294.

Updated the Ruby version in Step 9.

Added Step 10 to remove the 'pry-byebug' gem which depends on Ruby 2.0. Opted for this as it seems the most straight-forward and easiest change. Maybe I should add a note indicating that this is only for OpenShift production deployment, or is this fine?