add contribution from @joelhandwell to the README
add contribution from @joelhandwell to the README

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archsaber/chef-percona,twistle/chef-percona,twistle/chef-percona,Sauraus/chef-percona,notion/chef-percona,jharley/chef-percona,archsaber/chef-percona,Sauraus/chef-percona,phlipper/chef-percona,phlipper/chef-percona,jharley/chef-percona,notion/chef-percona