--([ For 0.4 ])----
- Reading from standard input when no FILE, or when FILE is -
- Make an informative man page
- Support -45 as -n 45
- Output the last N bytes
- Remove -v and only have --version for version
- Support +N as orint beginning with the Nth item from the start of each file.
- Support b for 512, k for 1024 and m for 1048576 as suffix for bytes.
- make -kf work. -fk works but -kf doesn't.