hide drafts button when the files collection does not have a _posts directory, closes #547
hide drafts button when the files collection does not have a _posts directory, closes #547

leohmoraes/prose,dereklieu/prose,thezawad/prose,anandthakker/prose,AtekiRyu/prose,simoneau/prose,mcanthony/prose,RRides/prose,thezawad/prose,obeninteractive/prose,webdev1001/prose,danieldelhoyo/prose,phillipadsmith/prose,xxdavidxx11/prose,bowtie-io/prose,dereklieu/prose,xxdavidxx11/prose,obeninteractive/prose,VictoriaLa/prose,RRides/prose,prose/prose,bowtie-io/prose,prose/prose,sudarshanReddykurri/prose,sudarshanReddykurri/prose,simoneau/prose,prose/prose,nexocentric/prose,michaelkirk/prose,dereklieu/prose,another-dave/prose,another-dave/prose,sammcj/prose,leohmoraes/prose,VictoriaLa/prose,edgemaster/prose,mcanthony/prose,michaelkirk/prose,edgemaster/prose,nexocentric/prose,sammcj/prose,AtekiRyu/prose,danieldelhoyo/prose,webdev1001/prose,phillipadsmith/prose