menumeters: fixed "undefined method `unshift' for nil:NilClass" by initializing if nil
menumeters: fixed "undefined method `unshift' for nil:NilClass" by initializing if nil

wendorf/sprout-osx-apps,1000Bulbs/pivotal_workstation,pivotal-sprout/sprout-osx-apps,pivotal-sprout/sprout-osx-apps,wendorf/sprout-osx-apps,se3000/pivotal_workstation,1000Bulbs/sprout,Yesware/sprout,1000Bulbs/sprout,Yesware/sprout,webcoyote/pivotal_workstation,Yesware/sprout,1000Bulbs/pivotal_workstation,pivotal-sprout/sprout-osx-apps,webcoyote/pivotal_workstation,wendorf/sprout-osx-apps,webcoyote/pivotal_workstation