Enable large stacks on 64-bit architectures
Make Bitv::eq_vec take ~[bool] rather than ~[uint]

Fixes #7711.
extend the iterator tutorial

documents conversion, size hints and double-ended iterators and adds
more of the traits to the prelude
Replace owned with borrowed pointer.

As pointed out by cmr, there's no need for it to be owned there.
That was also in the original scope of #7711.
auto merge of #7728 : bcully/rust/largestack64, r=cmr

Just to get the ball rolling, this patch sets stacks to 4 MB on >32-bit architectures.
auto merge of #7730 : chris-morgan/rust/bitv-eq_vec-bool, r=cmr

Fixes #7711.
Remove the global 'vec::to_owned' function
Account for possible 0-sized elements in vector iterators

Closes #7733
auto merge of #7736 : thestinger/rust/doc, r=thestinger

2b96408 r=sanxiyn

documents conversion, size hints and double-ended iterators and adds
more of the traits to the prelude