tail: Take ownership of the provided BufReader<T>
tail: Take ownership of the provided BufReader<T>

The `BufReader` argument passed to the `fn tail<T: Read>(&mut BufReader<T>,
settings: &settings)` function is never reused, so the `tail` function should
just take ownership of it.

kevgeniy/coreutils,uutils/coreutils,jbcrail/coreutils,Heather/coreutils,ebfe/coreutils,Heather/coreutils,kwantam/coreutils,keunwoo/coreutils,keunwoo/coreutils,kevgeniy/coreutils,uutils/coreutils,wimh/coreutils,ebfe/coreutils,Arcterus/coreutils,uutils/coreutils,tempbottle/coreutils,jbcrail/coreutils,wimh/coreutils,kwantam/coreutils,tempbottle/coreutils,Arcterus/coreutils