[BusyBox] bug#1052: obsolete option

[Matt Kraai]

Howdy,

According to the source of GNU tail, the -<number> option format is
obsolete.  And, furthermore, it is a pain to parse.  Given that busybox
head doesn't even make an attempt, and that there is a simple workaround
(-n), and that it will make the argument parsing code ugly, I'd like to
remove support for this option altogether.

All opposed?

Matt