fix mismatch with argument names for progress.bar
fix mismatch with argument names for progress.bar

nathancahill/clint,nathancahill/clint,kennethreitz/clint,glorizen/clint,Lh4cKg/clint,wkentaro/clint,tz70s/clint,wkentaro/clint,thusoy/clint,1gitGrey/clint,1gitGrey/clint