tail: suppress headers when --quiet flag is used

[shutefan]

A first stab at adding the --quiet flag to tail.

As mentioned in the TODOs the --silent alias is missing so far. Not sure how (and if) this is possible with getopts. If clap can do this it might be a good reason to move forward with #1006?

Another open point is taking the position of -q and -v into account. Again, not sure if this is even possible with getopts...

[Arcterus]

Thanks :)

I do not believe it's possible with getopts to create aliases or handle positions of arguments, like you said. This is part of the reason I started switching to clap in #1063.