Enable privacy check for enum methods.
Fix incorrect non-exhaustive matching for fixed length vecs

Code like this is fixed now:

```
fn foo(p: [u8, ..4]) {
    match p {
        [a, b, c, d] => {}
    };
}
```

Invalid constructors are not reported as errors yet:

```
fn foo(p: [u8, ..4]) {
    match p {
        [_, _, _] => {} // this should be error
        [_, _, _, _, _, .._] => {} // and this
        _ => {}
    }
}
```

Issue #8311 is partially fixed by this commit. Fixed-length arrays in
let statement are not yet allowed:

```
let [a, b, c] = [1, 2, 3]; // still fails
```
rust-mode: make indentation customizable

Add new variable rust-indent-offset, defaulting to
the old value, and use it.
typo in tutorial
Add #[inline] to impl Zero for ()

Follow-up to #8155
Allow attributes to appear as macro arguments

Fixes #8393
Isolate common wait_end logic
Implement `lower_bound_iter`/`upper_bound_iter` for TrieMap/TrieSet
Add parse-error recovery for erroneous `struct_id { }` form.

There are 4 different new tests, to check some different scenarios for
what the parse context is at the time of recovery, becasue our
compile-fail infrastructure does not appear to handle verifying
error-recovery situations.

Differentiate between unit-like struct definition item and unit-like
struct construction in the error message.

----

More generally, outlines a more generic strategy for parse error
recovery: By committing to an expression/statement at set points in
the parser, we can then do some look-ahead to catch common mistakes
and skip over them.

One detail about this strategy is that you want to avoid emitting the
"helpful" message unless the input is reasonably close to the case of
interest.  (E.g. do not warn about a potential unit struct for an
input of the form `let hmm = do foo { } { };`)

To accomplish this, I added (partial) last_token tracking; used for
`commit_stmt` support.

The check_for_erroneous_unit_struct_expecting fn returns bool to
signal whether it "made progress"; currently unused; this is meant for
use to compose several such recovery checks together in a loop.
Switch to using .enumerate() some places in _match.
Fix vector pattern matching. Closes #6909.
Implement an `address_insignificant` attribute

This can be applied to statics and it will indicate that LLVM will attempt to
merge the constant in .data with other statics.

I have preliminarily applied this to all of the statics generated by the new
`ifmt!` syntax extension. I compiled a file with 1000 calls to `ifmt!` and a
separate file with 1000 calls to `fmt!` to compare the sizes, and the results
were:

fmt           310k
ifmt (before) 529k
ifmt (after)  202k

This now means that ifmt! is both faster and smaller than fmt!, yay!
Fix some warnings.
rustc: Obey RUST_MIN_STACK env var

A lot of people are hitting stack overflows in rustc. This will make it
easier to experiment with stack size.
Fix interaction between default matches and guards. Closes #3121.
Elide unnecessary ret slot allocas

When there is only a single store to the ret slot that dominates the
load that gets the value for the "ret" instruction, we can elide the
ret slot and directly return the operand of the dominating store
instruction. This is the same thing that clang does, except for a
special case that doesn't seem to affect us.

Fixes #8238
auto merge of #8270 : dotdash/rust/ret_alloca_elim, r=pcwalton

When there is only a single store to the ret slot that dominates the
load that gets the value for the "ret" instruction, we can elide the
ret slot and directly return the operand of the dominating store
instruction. This is the same thing that clang does, except for a
special case that doesn't seem to affect us.

Fixes #8238
Mass rename of .consume{,_iter}() to .move_iter()

cc #7887
Clean up some unused imports in tests
std: merge iterator::DoubleEndedIterator and DoubleEndedIteratorUtil