librustc/libstd: No longer pass crate_map to start.
libstd/librustc: Make the crate_map a weak symbol that libstd links against.
tests: Remove crate_map from start.
Fix unresolved symbol error for the crate_map in libstd on os x.
More 0.8 release notes
auto merge of #9438 : brson/rust/relnotes, r=thestinger
Find the cratemap at runtime on windows.
auto merge of #9301 : luqmana/rust/ncm, r=brson

Get rid of the crate_map arg!

r? @brson
Add sundown to src/rt/

This also starts compiling it in the same manner as linenoise, it's just bundled
with librustrt directly, and we export just a few symbols out of it.
Use sundown for markdown highlighting in rustdoc

This takes rendering times of documentation down from 30s to 0.5s. Kinda sad
that none of the parallelism is needed, but oh well!

Closes #7380
cc #3546
Change all code-blocks in an automated fashion

    find src -name '*.rs' | xargs sed -i '' 's/~~~.*{\.rust}/```rust/g'
    find src -name '*.rs' | xargs sed -i '' 's/ ~~~$/ ```/g'
    find src -name '*.rs' | xargs sed -i '' 's/^~~~$/ ```/g'
Enable various useful markdown extensions
Improve comment stripping for rustdoc.

There is less implicit removal of various comment styles, and it also removes
extraneous stars occasionally found in docblock comments. It turns out that the
bug for getops was just a differently formatted block.

Closes #9425
Closes #9417
Add the ability to list all passes in rustdoc

In doing so, also remove the collapse-privacy pass because it's a little
over-zealous and may not be right 100% of the time (not used right now as well)