Refactor trans_call to separate out the translation of the arguments, environment, and return pointer
core: rename vec::rev_each{,i} to vec::each{,i}_reverse

I'm making this change because the _reverse suffix is more commonly
used in libcore/libstd.
core: add char_at_reverse
core: add char_len method
core: add str::each{,i}_reverse
librustc: Remove debug code and add scary warnings for rusti/rustpkg
auto merge of #5450 : pcwalton/rust/warnings, r=graydon

r? @graydon
auto merge of #5445 : nikomatsakis/rust/issue-3678-refactor-trans_call, r=graydon

Refactor trans_call to separate out the translation of the arguments, environment, and return pointer.  Towards #3678.  r? @brson
testsuite: Add test for #4210
core: add Reader, Writer, ReaderUtil, WriterUtil to prelude. Close #4182.
add stage3 markers where necessary for dist-snap
libsyntax: Never use `::<>` in the type grammar
librustc: Fix bug preventing `-framework Foo` from working cross-crate.
auto merge of #5453 : catamorphism/rust/issue-4120, r=catamorphism
etc: Suppress Linux valgrind issues for new scheduler
auto merge of #5447 : erickt/rust/incoming, r=graydon

This normalizes the how we call reverse iteration functions. It also adds a char_len method, and a method to iterate backwards over a string.
auto merge of #5455 : pcwalton/rust/framework, r=catamorphism

r? @catamorphism
renamed str::view -> slice_DBG_BRWD
renamed str::slice -> slice_DBG_UNIQ
changed vec slice method -> to_owned()
renamed vec view method  -> slice_V_DBG_BRWD
auto merge of #5456 : graydon/rust/fixups, r=pcwalton

Stage markers for stage3 and a trivial prelude fix.
auto merge of #5458 : pcwalton/rust/valgrind-suppress, r=pcwalton