Add basic documentation for with_capacity
Move documentation for vec::windowed where it will be generated
Rename vec::mod2 to vec::mod_zip
rt: pull upstream ISAAC code for consistency between 32/64 bit platforms

The "unsigned 4 byte" `ub4`s are actually 8 bytes on 64-bit platforms
which mean that some bits > 2**32 were retained in calculations, these
would then "reappear" after a shift and so the stream of random numbers
would differ on 32 bit vs 64 bit platforms.
Made fail! and assert! accept both &'static str and ~str, as well as a fmt! like format list.

Unwinding through macros now happens as a call to the trait function `FailWithCause::fail_with()`, which consumes self, allowing to use a more generic failure object in the future.
implement Ord, TotalEq and TotalOrd for char

Closes #6063
auto merge of #6055 : cmr/rust/incoming, r=graydon,brson
Added test cases for all fail message formats
rt: use the [u]int[nn]_t types in the RNG.

This means that `ub4`s are always 4 bytes, rather than being 8 bytes on
x64. (Suggested but not implemented by upstream: "Porting it to a 64-bit
machine [...] may just need an adjustment of the definition of ub4")
Suppress all 'cond' errors in valgrind. #5856
auto merge of #6077 : brson/rust/valgrind, r=brson
auto merge of #6057 : cmr/rust/map_zip, r=graydon

I think the name is more clear, and fits with filter_map etc.
auto merge of #6058 : huonw/rust/rt-isaac-update, r=graydon

The "unsigned 4 byte" `ub4`s are actually 8 bytes on 64-bit platforms
which mean that some bits > 2**32 were retained in calculations, these
would then "reappear" after a right shift and so the stream of random numbers
would differ on 32 bit vs 64 bit platforms.

http://burtleburtle.net/bob/c/randport.c
auto merge of #6059 : Kimundi/rust/nice-fail, r=pcwalton

r? @brson

Unwinding through macros now happens as a call to the trait function `FailWithCause::fail_with()`, which consumes self, allowing to use a more generic failure object in the future.
auto merge of #6064 : thestinger/rust/char, r=catamorphism