Modified Gemfile to lock the version of ruby gem rack to avoid gem install failure on ruby version less than 2.2.
Modified Gemfile to lock the version of ruby gem rack to avoid gem install failure on ruby version less than 2.2.

chef/knife-ec2,MsysTechnologiesllc/knife-ec2,MsysTechnologiesllc/knife-ec2,chef/knife-ec2,ClogenyTechnologies/knife-ec2