Avoid setting content-disposition header to images. Also deliver download...

Avoid setting content-disposition header to images. Also deliver download files with original file name.

lib/fileUpload.coffee

@@ -39,7 +39,8 @@ if UploadFS?
 			onFinishUpload: ->
 				console.log arguments
 			onRead: (fileId, file, req, res) ->
-				res.setHeader 'content-disposition', 'download'
+				unless file?.type?.match(/^image\/.*/)
+					res.setHeader 'content-disposition', "attachment; filename='#{ file.name }'"
 
 	if Meteor.isServer
 		initFileStore()