Disable ETag for `res.sendFile()`

[ritch]

res.sendFile() accepts an option to disable ETags. It would make sense that app.disable('etag') sets sendFile()s options.etag to false for you. This is a breaking change so it would have to wait for 5.x.

[ilanbiala]

@ritch did this make it into 5.x already?

[dougwilson]

Hi @ilanbiala you can look at #2237 to see what has been checked off. The answer for this is no, especially since there is not hard date for 5.0 yet.