Poly and String have polymorphic `impl`s and so require different method
names.

* Stop referencing io_error
* Start changing "Failure" sections to "Error" sections
* Update all doc examples to work.

* All I/O now returns IoResult<T> = Result<T, IoError>
* All formatting traits now return fmt::Result = IoResult<()>
* The if_ok!() macro was added to libstd

These are either returned from public functions, and really should
appear in the documentation, but don't since they're private, or are
implementation details that are currently public.

The following are renamed:

* `min_value` => `MIN`
* `max_value` => `MAX`
* `bits` => `BITS`
* `bytes` => `BYTES`

Fixes #10010.

[std::str] Rename from_utf8_owned_opt() to from_utf8_owned(), drop the old from_utf8_owned() behavior

Rename existing iterators to get rid of the Iterator suffix and to
give them names that better describe the things being iterated over.

* Reexport io::mem and io::buffered structs directly under io, make mem/buffered
  private modules
* Remove with_mem_writer
* Remove DEFAULT_CAPACITY and use DEFAULT_BUF_SIZE (in io::buffered)

The `print!` and `println!` macros are now the preferred method of printing, and so there is no reason to export the `stdio` functions in the prelude. The functions have also been replaced by their macro counterparts in the tutorial and other documentation so that newcomers don't get confused about what they should be using.

This is just an unnecessary trait that no one's ever going to parameterize over
and it's more useful to just define the methods directly on the types
themselves. The implementors of this type almost always don't want
inner_mut_ref() but they're forced to define it as well.

Closes #11372

Conflicts:
	src/librustc/middle/lint.rs

Closes #11232.

These methods are sorely needed on readers and writers, and I believe that the
encoding story should be solved with composition. This commit adds back the
missed functions when reading/writing strings onto generic Readers/Writers.

Closes #11234

All tests except for the homing tests are now working again with the
librustuv/libgreen refactoring. The homing-related tests are currently commented
out and now placed in the rustuv::homing module.

I plan on refactoring scheduler pool spawning in order to enable more homing
tests in a future commit.

This commit brings the library up-to-date in order to get all tests passing
again

This commit introduces a new crate called "native" which will be the crate that
implements the 1:1 runtime of rust. This currently entails having an
implementation of std::rt::Runtime inside of libnative as well as moving all of
the native I/O implementations to libnative.

The current snag is that the start lang item must currently be defined in
libnative in order to start running, but this will change in the future.

Cool fact about this crate, there are no extra features that are enabled.

Note that this commit does not include any makefile support necessary for
building libnative, that's all coming in a later commit.

I accidentally removed this module from compilation awhile back, this adds it
back in.

Closes #11076

This adds a bunch of useful Reader and Writer implementations. I'm not a
huge fan of the name `util` but I can't think of a better name and I
don't want to make `std::io` any longer than it already is.

Also remove all instances of 'self within the codebase.

This fixes #10889.

-   `Buffer.lines()` returns `LineIterator` which yields line using
    `.read_line()`.
-   `Reader.bytes()` now takes `&mut self` instead of `self`.
-   `Reader.read_until()` swallows `EndOfFile`. This also affects
    `.read_line()`.

cells.

This reverts commit c54427dd.

Leave the #[ignores] in that were added to rustpkg tests.

Conflicts:
	src/librustc/driver/driver.rs
	src/librustc/metadata/creader.rs