Fix typo in to_digit
Bump required pandoc version to 1.9.

Earlier versions of pandoc don't have the default.html5 and thus,
building the docs fail.

Signed-off-by: Noufal Ibrahim <noufal@nibrahim.net.in>
Use consistent capitalization in makefile errors

In Rust we don't like capital letters.
Fix installation with DESTDIR
auto merge of #10222 : nibrahim/rust/docfix, r=brson

Earlier versions of pandoc don't have the `default.html5` template file. When `make docs` is run, the build process fails with this message.

    pandoc: doc/rust.html
    pandoc: /usr/share/pandoc-1.8.2.1/templates/default.html5: openFile: does not exist (No such file or directory)
    
    node.js:201
            throw e; // process.nextTick error, or 'error' event on first tick
                  ^
    Error: write EPIPE
        at errnoException (net.js:670:11)
        at Object.afterWrite [as oncomplete] (net.js:503:19)
    make: *** [doc/rust.html] Error 1
auto merge of #10232 : brson/rust/destdir, r=thestinger
Rustdoc: Properly strip private modules

A private module will survive the strip-private pass if it contains
trait implementations, which aren't stripped until a separate pass in
render.
auto merge of #10225 : Jurily/rust/master, r=alexcrichton
auto merge of #10229 : brson/rust/warnings, r=thestinger

In Rust we don't like capital letters.
auto merge of #10230 : alexcrichton/rust/snapshots, r=brson

Closes #2240
auto merge of #10233 : sfackler/rust/private-module, r=alexcrichton

A private module will survive the strip-private pass if it contains
trait implementations, which aren't stripped until a separate pass in
render.
Move rt::io traits into the prelude

These traits belong here, and were simply waiting for the std::io traits to get
removed. It's time they take their rightful positions!
Modify IoFactory's fs_mkdir, and add fs_rename

The invocation for making a directory should be able to specify a mode to make
the directory with (instead of defaulting to one particular mode). Additionally,
libuv and various OSes implement efficient versions of renaming files, so this
operation is exposed as an IoFactory call.
Remove all blocking std::os blocking functions

This commit moves all thread-blocking I/O functions from the std::os module.
Their replacements can be found in either std::rt::io::file or in a hidden
"old_os" module inside of native::file. I didn't want to outright delete these
functions because they have a lot of special casing learned over time for each
OS/platform, and I imagine that these will someday get integrated into a
blocking implementation of IoFactory. For now, they're moved to a private module
to prevent bitrot and still have tests to ensure that they work.

I've also expanded the extensions to a few more methods defined on Path, most of
which were previously defined in std::os but now have non-thread-blocking
implementations as part of using the current IoFactory.

The api of io::file is in flux, but I plan on changing it in the next commit as
well.

Closes #10057
Fill out the remaining functionality in io::file

This adds bindings to the remaining functions provided by libuv, all of which
are useful operations on files which need to get exposed somehow.

Some highlights:

* Dropped `FileReader` and `FileWriter` and `FileStream` for one `File` type
* Moved all file-related methods to be static methods under `File`
* All directory related methods are still top-level functions
* Created `io::FilePermission` types (backed by u32) that are what you'd expect
* Created `io::FileType` and refactored `FileStat` to use FileType and
  FilePermission
* Removed the expanding matrix of `FileMode` operations. The mode of reading a
  file will not have the O_CREAT flag, but a write mode will always have the
  O_CREAT flag.

Closes #10130
Closes #10131
Closes #10121
Move io::file to io::fs and fns out of File

This renames the `file` module to `fs` because that more accurately describes
its current purpose (manipulating the filesystem, not just files).

Additionally, this adds an UnstableFileStat structure as a nested structure of
FileStat to signify that the fields should not be depended on. The structure is
currently flagged with #[unstable], but it's unlikely that it has much meaning.