Display progress bar when downloading

Cellar/homebrew/brewkit.rb

@@ -122,7 +122,7 @@ protected
   def fetch
     tgz=File.expand_path File.basename(@url)
     unless File.exists? tgz
-      `curl -LOA "#{$agent}" "#{@url}"`
+      `curl -#LOA "#{$agent}" "#{@url}"`
       raise "Download failed" unless $? == 0
     end
     return tgz