Document std::ops.

Added an overview with a 'real' example, as well as toy implementations of all of
the traits.

Closes #9356.
Add get_opt to std::vec
std::iter: Introduce .by_ref() adaptor

Creates a wrapper around a mutable reference to the iterator.

This is useful to allow applying iterator adaptors while still
retaining ownership of the original iterator value.

Example::

   let mut xs = range(0, 10);
   // sum the first five values
   let partial_sum = xs.by_ref().take(5).fold(0, |a, b| a + b);
   assert!(partial_sum == 10);
   // xs.next() is now `5`
   assert!(xs.next() == Some(5));
std: Replace num::IntConvertible with {To,From}Primitive
syntax: Add #[deriving(FromPrimitive)] syntax extension

Right now this only works for c-style enums.
syntax: swap from .span_fatal to .span_err in #[deriving(FromPrimitive)]
test: add compile-fail test for #[deriving(FromPrimitive)]
std: Swap {To,From}Primitive to use the 64bit as the unimplemented version

One downside with this current implementation is that since BigInt's
default is now 64 bit, we can convert larger BigInt's to a primitive,
however the current implementation on 32 bit architectures does not
take advantage of this fact.
extra: Add ToBigInt and ToBigUint traits
Package system runtime dependencies into snapshots
Package system runtime dependencies into Windows distribution.
Correctly report errors for ambiguous default methods
Use the correct logging crate while monomorphing

This makes sure that the top-level crate name is correct when emitting log
statements for a monomorphized function in another crate. This happens by
tracing the monomorphized ID back to the external source and then using that
crate index to get the name of the crate.

Closes #3046
Document logging and remove old functions

This adds a large doc-block to the top of the std::logging module explaining how
to use it. This is mostly just making sure that all the information in the
manual's section about logging is also here (in case someone decides to look
into this module first).

This also removes the old console_{on,off} methods. As far as I can tell, the
functions were only used by the compiler, and there's no reason for them to be
used because they're all turned off by default anyway (maybe they were turned on
by default at some point...)

I believe that this is the final nail in the coffin and closes #5021
rustdoc: Document what's going on throughout

This addresses some of @huonw's in #9691 about the startling lack of
documentation guiding one throughout the innards of rustdoc::html
Rewrite lint passes with less visitor cruft

This purges about 500 lines of visitor cruft from lint passes. All lints are
handled in a much more sane way at this point. The other huge bonus of this
commit is that there are no more @-boxes in the lint passes, fixing the 500MB
memory regression seen when the lint passes were refactored.

Closes #8589
auto merge of #9686 : alexcrichton/rust/lint, r=thestinger

This purges about 500 lines of visitor cruft from lint passes. All lints are
handled in a much more sane way at this point. The other huge bonus of this
commit is that there are no more @-boxes in the lint passes, fixing the 500MB
memory regression seen when the lint passes were refactored.

Closes #8589
Update std::ops docs as per feedback

from @chris-morgan
auto merge of #9522 : steveklabnik/rust/doc_std_opts, r=alexcrichton

Added an overview with a 'real' example, as well as toy implementations of all of
the traits.

Closes #9356.
extra: remove unnecessary second level functions

do_strptime() and do_strftime()