Update CONTRIBUTING.md to discuss testing
Update CONTRIBUTING.md to discuss testing

CommandPost/CommandPost-App,asmagill/hammerspoon,heptal/hammerspoon,cmsj/hammerspoon,Habbie/hammerspoon,latenitefilms/hammerspoon,wvierber/hammerspoon,chrisjbray/hammerspoon,bradparks/hammerspoon,Habbie/hammerspoon,zzamboni/hammerspoon,heptal/hammerspoon,knu/hammerspoon,Hammerspoon/hammerspoon,cmsj/hammerspoon,zzamboni/hammerspoon,latenitefilms/hammerspoon,kkamdooong/hammerspoon,zzamboni/hammerspoon,latenitefilms/hammerspoon,latenitefilms/hammerspoon,asmagill/hammerspoon,cmsj/hammerspoon,junkblocker/hammerspoon,lowne/hammerspoon,wvierber/hammerspoon,knu/hammerspoon,Hammerspoon/hammerspoon,bradparks/hammerspoon,Hammerspoon/hammerspoon,wvierber/hammerspoon,asmagill/hammerspoon,Habbie/hammerspoon,CommandPost/CommandPost-App,Hammerspoon/hammerspoon,junkblocker/hammerspoon,cmsj/hammerspoon,bradparks/hammerspoon,kkamdooong/hammerspoon,chrisjbray/hammerspoon,knu/hammerspoon,wvierber/hammerspoon,chrisjbray/hammerspoon,lowne/hammerspoon,latenitefilms/hammerspoon,lowne/hammerspoon,chrisjbray/hammerspoon,chrisjbray/hammerspoon,latenitefilms/hammerspoon,zzamboni/hammerspoon,asmagill/hammerspoon,kkamdooong/hammerspoon,Habbie/hammerspoon,junkblocker/hammerspoon,kkamdooong/hammerspoon,bradparks/hammerspoon,Habbie/hammerspoon,bradparks/hammerspoon,junkblocker/hammerspoon,heptal/hammerspoon,lowne/hammerspoon,knu/hammerspoon,chrisjbray/hammerspoon,knu/hammerspoon,heptal/hammerspoon,cmsj/hammerspoon,zzamboni/hammerspoon,heptal/hammerspoon,knu/hammerspoon,Hammerspoon/hammerspoon,Hammerspoon/hammerspoon,CommandPost/CommandPost-App,CommandPost/CommandPost-App,zzamboni/hammerspoon,wvierber/hammerspoon,asmagill/hammerspoon,CommandPost/CommandPost-App,Habbie/hammerspoon,asmagill/hammerspoon,lowne/hammerspoon,junkblocker/hammerspoon,CommandPost/CommandPost-App,kkamdooong/hammerspoon,cmsj/hammerspoon