Took initial_tab and subsequent_tab away from the fill() method and

Took initial_tab and subsequent_tab away from the fill() method and
transformed them into the initial_indent and subsequent_indent instance
attributes.  Now they actually work as advertised, ie. they are
accounted for in the width of each output line.  Plus you can use them
with wrap() as well as fill(), and fill() went from simple-and-broken to
trivial-and-working.