librustc: Remove `use mod` from the language
libstd: correct bigint's quot/rem, div/modulo
Revert "Errors with the same span print the span once"

This reverts commit 6030e3982a52c8d9ede225f992088bb75fba4ef1.
docs: Sketch out rustpkg manual
rustpkg: In doc, mention other implicit RUST_PATH entries

as per Graydon's comment
auto merge of #6007 : pcwalton/rust/use-mod, r=brson

r? @brson
core: ignore test from_str_ignore_underscores. Broken on i686. #6018
test: fix for missing ARM support
auto merge of #6019 : brson/rust/xfail, r=brson
auto merge of #6013 : gifnksm/rust/bigint-quot-rem, r=graydon

BigInt had been supported quot/rem and div/mod correctly, but after merging #5990 they have been broken.
This commit fixes it.
Remove a stray new operator in rust_task.h
auto merge of #6015 : catamorphism/rust/rustpkg-doc-second-try, r=catamorphism

r? @graydon

Only change from the version that you read is that I addressed your comment about `RUST_PATH`.
Use correct grammar for error message.

When the number of parameters is 1, then 'parameter' should remain singular.
Otherwise pluralize it.
Use backticks for the unsafe keyword in error messages
auto merge of #6017 : brson/rust/revert-span-merge, r=catamorphism

This reverts commit 6030e3982a52c8d9ede225f992088bb75fba4ef1.

This reorders error messages in ways that aren't intended. A more satisfying solution will require an interface that allows diagnostics to be grouped together, so that messages that logically belong together aren't reordered.

#4569
auto merge of #6020 : yichoi/rust/pull-0423, r=brson

fix for missing ARM support to pass make stage of rpass
auto merge of #6025 : alexcrichton/rust/issue-2697, r=catamorphism

Closes #2697

I guess all of the uses weren't around any more, because everything continued to compile (at least on OSX). If bors doesn't like it for another platform I can try to track it down as well.
Attempt to fix x86 only strconv test failure
auto merge of #6026 : isanbard/rust/ca73fbf72615575f106ee18160580711aca89d85, r=catamorphism

When the number of parameters is 1, then 'parameter' should remain singular.
Otherwise pluralize it.
auto merge of #6027 : alexcrichton/rust/more-backticks, r=catamorphism

It seems that the general convention of error messages is to have keywords in backticks, so it's probably a good idea to keep doing that.