strconv: QuoteToGraphic documentation on ASCII is wrong

[pascaldekloe]

QuoteToGraphic returns a double-quoted Go string literal representing s. The returned string uses Go escape sequences (\t, \n, \xFF, \u0100) for non-ASCII characters and non-printable characters as defined by IsGraphic.

The documentation reads like non-ASCII characters are escaped, and they are not. I'm not even sure that the mention of ASCII was ment to say here.

[gopherbot]

Change https://golang.org/cl/216478 mentions this issue: strconv: stop describing Unicode graphic characters as non-ASCII

[pascaldekloe]

Thanks @ianlancetaylor.