Conflicts:
	src/libcore/atomic.rs
	src/libcore/finally.rs
	src/test/auxiliary/inherited_stability.rs
	src/test/auxiliary/lint_stability.rs

This PR introduces `isize` and `usize` modules to `core` and `std`, and
deprecates the existing `int` and `uint` modules. The rustdoc primitive
type links now point to these new modules.

Due to deprecation this is a:

[breaking-change]

This small patch stabilizes the names of all integer modules (including
`int` and `uint`) and the `MIN` and `MAX` constants. The `BITS` and
`BYTES` constants are left unstable for now.

followed by a semicolon.

This allows code like `vec![1i, 2, 3].len();` to work.

This breaks code that uses macros as statements without putting
semicolons after them, such as:

    fn main() {
        ...
        assert!(a == b)
        assert!(c == d)
        println(...);
    }

It also breaks code that uses macros as items without semicolons:

    local_data_key!(foo)

    fn main() {
        println("hello world")
    }

Add semicolons to fix this code. Those two examples can be fixed as
follows:

    fn main() {
        ...
        assert!(a == b);
        assert!(c == d);
        println(...);
    }

    local_data_key!(foo);

    fn main() {
        println("hello world")
    }

RFC #378.

Closes #18635.

[breaking-change]

The following are unstable:

- core::int, i8, i16, i32, i64
- core::uint, u8, u16, u32, u64
- core::int::{BITS, BYTES, MIN, MAX}, etc.
- std::int, i8, i16, i32, i64
- std::uint, u8, u16, u32, u64

The following are experimental:
- std::from_str::FromStr and impls - may need to return Result instead of Option
- std::int::parse_bytes, etc. - ditto
- std::num::FromStrRadix and impls - ditto
- std::num::from_str_radix - ditto

The following are deprecated:
- std::num::ToStrRadix and imples - Wrapper around fmt::radix. Wrong name (Str vs String)

See https://github.com/rust-lang/rust/wiki/Meeting-API-review-2014-06-23#uint

This commit adds support in rustdoc to recognize the `#[doc(primitive = "foo")]`
attribute. This attribute indicates that the current module is the "owner" of
the primitive type `foo`. For rustdoc, this means that the doc-comment for the
module is the doc-comment for the primitive type, plus a signal to all
downstream crates that hyperlinks for primitive types will be directed at the
crate containing the `#[doc]` directive.

Additionally, rustdoc will favor crates closest to the one being documented
which "implements the primitive type". For example, documentation of libcore
links to libcore for primitive types, but documentation for libstd and beyond
all links to libstd for primitive types.

This change involves no compiler modifications, it is purely a rustdoc change.
The landing pages for the primitive types primarily serve to show a list of
implemented traits for the primitive type itself.

The primitive types documented includes both strings and slices in a semi-ad-hoc
way, but in a way that should provide at least somewhat meaningful
documentation.

Closes #14474

Closes #12925

This mostly involved frobbing imports between realstd, realcore, and the core
being test. Some of the imports are a little counterintuitive, but it mainly
focuses around libcore's types not implementing Show while libstd's types
implement Show.

This implements all traits inside of core::num for all the primitive types,
removing all the functionality from libstd. The std modules reexport all of the
necessary items from the core modules.

See #11273 and #13318

Closes #2569

Issue #1457

Also rename `next_power_of_two_opt` to `checked_next_power_of_two`.

`Times::times` was always a second-class loop because it did not support the `break` and `continue` operations. Its playful appeal was then lost after `do` was disabled for closures. It's time to let this one go.

The following are renamed:

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

Fixes #10010.

One less trait in std::num, and three less exported in the prelude.

This commit uniforms the short title of modules provided by libstd,
in order to make their roles more explicit when glancing at the index.
Signed-off-by: NLuca Bruno <lucab@debian.org>

compile-fail tests, run-fail tests, and run-pass tests.

Like next_power_of_two, but returns None on overflow.

This follows the same pattern as the other numeric trait impls, and reduces the clutter in std::num.

Moves the Times trait to num while the question of whether it should
exist at all gets hashed out as a completely separate question.

Change the former repetition::

    for 5.times { }

to::

    do 5.times { }

.times() cannot be broken with `break` or `return` anymore; for those
cases, use a numerical range loop instead.