add Response#setEncoding

[tellnes]

[Jxck]

+1

[acgray]

+1

[kumavis]

better than nothing +1

[guasek]

+1

[tellnes]

I'll rebase this if one with commit bit says it will be merged.

[shergin]

+1

[saiichihashimoto]

+3

[patrickmetz]

One can at least put the following code into lib/response.js, to make the error disappear:

Response.prototype.setEncoding = function(encoding) { // not implemented }

If needed, you have to handle the encoding elsewhere, because that would need further changes in http-browserify.