auto merge of #12861 : huonw/rust/lint-owned-vecs, r=thestinger
auto merge of #12861 : huonw/rust/lint-owned-vecs, r=thestinger

lint: add lint for use of a `~[T]`.

This is useless at the moment (since pretty much every crate uses
`~[]`), but should help avoid regressions once completely removed from a
crate.

shepmaster/rand,bhickey/rand,achanda/rand,GrahamDennis/rand,arthurprs/rand,bluss/rand,waynenilsen/rand,huonw/rand,retep998/rand,ebfull/rand