Add HashSet::with_capacity_and_keys() function

This function can be use to create HashSets before the tls is
initialized.
Rewrite fileinput tests to use std::rt::io

These tests are being very flaky on the bots, and the reason is that files are
being created and then when attempted to get read they actually don't exist. I'm
not entirely sure why this is happening, but I also don't fully trust the
std::io implemention using @-boxes to close/flush/write files at the right time.

This moves the tests to using std::rt::io which is hopefully more robust and
something that we can actually reason about. Sadly, due to #8810, these tests
fail on windows, so they're all ignored on windows right now.
Convert rust_crate_map.cpp to Rust

Conflicts:
	src/libstd/rt/logging.rs
Fix rustpkg install for git repositories
auto merge of #9087 : fhahn/rust/rust_crate_map, r=brson

This patch converts the rust_crate_map.cpp to Rust as mentioned at the end of #8880.
auto merge of #9148 : jakub-/rust/rustpkg-install-mkdir-p, r=catamorphism

Testing this is a little tricky as an intermediate temporary directory is only used for remote git repositories and therefore that path cannot be reliably exercised in the tests.
auto merge of #9141 : alexcrichton/rust/ignore-fileinput, r=catamorphism

These tests are being very flaky on the bots, and the reason is that files are
being created and then when attempted to get read they actually don't exist. I'm
not entirely sure why this is happening, but I also don't fully trust the
std::io implemention using @-boxes to close/flush/write files at the right time.

This moves the tests to using std::rt::io which is hopefully more robust and
something that we can actually reason about. Sadly, due to #8810, these tests
fail on windows, so they're all ignored on windows right now.
fix handling of function attributes

The `noalias` attributes were being set only on function definitions,
not on all declarations. This is harmless for `noalias`, but prevented
some optimization opportunities and is *not* harmless for other
attributes like `sret` with ABI implications.

Closes #9104
set sret attribute as needed on call instructions

Since function pointers do not carry along the function attributes with
them in the type, this needs to be set on the call instruction itself.

Closes #9152
add sret + noalias to the out pointer parameter

This brings Rust in line with how `clang` handles return pointers.

Example:

    pub fn bar() -> [uint, .. 8] {
        let a = [0, .. 8];
        a
    }

Before:

    ; Function Attrs: nounwind uwtable
    define void @_ZN3bar17ha4635c6f704bfa334v0.0E([8 x i64]* nocapture, { i64, %tydesc*, i8*, i8*, i8 }* nocapture readnone) #1 {
    "function top level":
      %a = alloca [8 x i64], align 8
      %2 = bitcast [8 x i64]* %a to i8*
      call void @llvm.memset.p0i8.i64(i8* %2, i8 0, i64 64, i32 8, i1 false)
      %3 = bitcast [8 x i64]* %0 to i8*
      call void @llvm.memcpy.p0i8.p0i8.i64(i8* %3, i8* %2, i64 64, i32 8, i1 false)
      ret void
    }

After:

    ; Function Attrs: nounwind uwtable
    define void @_ZN3bar17ha4635c6f704bfa334v0.0E([8 x i64]* noalias nocapture sret, { i64, %tydesc*, i8*, i8*, i8 }* nocapture readnone) #1 {
    "function top level":
      %2 = bitcast [8 x i64]* %0 to i8*
      call void @llvm.memset.p0i8.i64(i8* %2, i8 0, i64 64, i32 8, i1 false)
      ret void
    }

Closes #9072
Closes #7298
remove unused `FastCall` wrapper

this can just be done using CallWithConv
teach Call/CallWithConv to set attributes
mark ~T ret values from function ptrs as noalias

Closes #9154
fix style in `trans_external_path`
document the register_fn split
document why attributes are set on CallInst