Consolidate documentation for -H option

Signed-off-by: Ben Firshman <ben@firshman.co.uk>
Remove newline from -G option

This is nowhere near 80 characters, and just makes it harder to read. Some
more work is needed to move the defaults from left-hand column to the
right-hand column which will make wrapping to 80 characters possible.

Signed-off-by: Ben Firshman <ben@firshman.co.uk>