librustc: Change i1 to i8 for bools. Attempts to put out burning tree. rs=burningtree
remove issue #3148 workarounds (no longer needed)
treemap: get rid of some implicit vector copies
get rid of implicit vec copies in treemap iterator

Each call to next() was doing a copy rather than a move. There's
currently no way for this to be a method that uses &mut self, so it has
to be a free function. Closes #4763.
update treemap FIXME
treemap: make map_next and set_next public
remove old snapshot workaround from smallintmap