Increase system stack size.
Mass rename of .consume{,_iter}() to .move_iter()

cc #7887
Clean up some unused imports in tests
std: merge iterator::DoubleEndedIterator and DoubleEndedIteratorUtil
std: merge Iterator and IteratorUtil
std: Rename Iterator.transform -> .map

cc #5898
std: Iterator.take_ -> .take
std: Iterator.flat_map_ -> .flat_map
std: Iterator.chain_ -> .chain
std: Iterator.last_ -> .last
std: Iterator.len_ -> .len
std: Transform.find_ -> .find
std: fix the non-stage0 str::raw::slice_bytes which broke in a merge
syntax and rustc: fix some warnings
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
Isolate common wait_end logic
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
```
Implement `lower_bound_iter`/`upper_bound_iter` for TrieMap/TrieSet
rust-mode: make indentation customizable

Add new variable rust-indent-offset, defaulting to
the old value, and use it.