chore(package): update async to version 2.0.0
chore(package): update async to version 2.0.0

https://greenkeeper.io/
mrwolfyu/meteo-bbb,vymarkov/hackathon-starter,bowdenk7/express-typescript-starter,Yixuan-Angela/hackathon-starter,peterblazejewicz/hackathon-starter,ericmreid/pingypong,cwesno/app_for_us,ReadingPlus/flog,stenio123/ai-hackathon,pvijeh/node-express-mongo-api,ahng1996/balloon-fight,teogenesmoura/SoftwareEng12016,quazar11/portfolio,Carlosreyesk/boards-api,mostley/backstab,dborncamp/shuttles,vymarkov/hackathon-starter,IsaacHardy/HOCO-FF-APP,devneel/spitsomebars,ReadingPlus/flog,ajijohn/brainprinter,awarn/bitcoins-trader,awarn/cashier-analytics,cwesno/app_for_us,colleenDunlap/Lake-Map,colleenDunlap/Lake-Map,gurneyman/riToolkit,ajijohn/brainprinter,Carlosreyesk/boards-api,Yixuan-Angela/hackathon-starter,EvelynSun/fcc-vote1,tendermario/binners-project,crystalrood/piggie,ericmreid/pingypong,HappyGenes/HappyGenes,ahng1996/balloon-fight,awarn/cashier-analytics,wfpc92/cleansuit-backend,IsaacHardy/HOCO-FF-APP,OperationSpark/Hackathon-Angel,colleenDunlap/PlayingOnInternet,peterblazejewicz/hackathon-starter,CAYdenberg/wikode,HappyGenes/HappyGenes,niallobrien/hackathon-starter-plus,CahalKearney/node-boilerplate,erood/creepy_ghost,dafyddPrys/contingency,gurneyman/riToolkit,mostley/backstab,teogenesmoura/SoftwareEng12016,bowdenk7/express-typescript-starter,pvijeh/node-express-mongo-api,ak-zul/hackathon-starter,erood/creepy_ghost,niallobrien/hackathon-starter-plus,quazar11/portfolio,CahalKearney/node-boilerplate,wfpc92/cleansuit-backend,dafyddPrys/contingency,hect1c/front-end-test,ajijohn/brainprinter,devneel/spitsomebars,crystalrood/piggie,tendermario/binners-project,sahat/hackathon-starter,OperationSpark/Hackathon-Angel,erood/weight_tracker_app,JessedeGit/vegtable,ak-zul/hackathon-starter,bowdenk7/express-typescript-starter,JessedeGit/vegtable,stenio123/ai-hackathon,colleenDunlap/PlayingOnInternet,colleenDunlap/PlayingOnInternet,erood/weight_tracker_app,awarn/bitcoins-trader,ajijohn/brainprinter,peterblazejewicz/hackathon-starter,crystalrood/piggie,LucienBrule/carpool,LucienBrule/carpool,dborncamp/shuttles,CAYdenberg/wikode,colleenDunlap/Lake-Map,sahat/hackathon-starter,mrwolfyu/meteo-bbb,hect1c/front-end-test,sahat/hackathon-starter,EvelynSun/fcc-vote1