Visit type parameter in lifetime suggestion

Previously, Rebuilder did not visit type parameters when rebuilding
generics and path, so in some cases the suggestion turns out to be
erroneous.
Add draft 0.10 release notes
dist: Add libbacktrace to source tarballs
mk: distcheck --uninstall
vec: convert `append` and `append_one` to methods

These were only free functions on `~[T]` because taking self by-value
used to be broken.
mk: Workaround distcheck failure on mac. #13224

Mac can't actually build our source tarballs because it's `tar`
command doesn't support the --exclude-vcs flag. This is just
a workaround to make our mac nightlies work (we get our source
tarballs from the linux bot).
auto merge of #13221 : thestinger/rust/append, r=alexcrichton

These were only free functions on `~[T]` because taking self by-value
used to be broken.
auto merge of #13223 : brson/rust/dist, r=alexcrichton
Json doesn't need to depend on IoError to implement Encodable #13230
auto merge of #13230 : Kroisse/rust/encodable-json, r=erickt

The implementation of `Encodable<E, S>` for `Json` doesn't need to assume `S` to be `IoError`, only the default encoders for `Json` are depend on it. So this can be parametrize to increase flexiblity. If not, types that implement `Encoder<E>` where `E` is not `IoError` can't be worked with `Json`.
auto merge of #13189 : alexcrichton/rust/relnotes, r=brson
rustc: Switch struct fields to private by default

This commit switches privacy's checking of fields to have *all* fields be
private by default. This does not yet change tuple structs, this only affects
structs with named fields. The fallout of this change will follow shortly.

RFC: 0004-private-fields

cc #8122
Closes #11809
Bump version to 0.10
num: rm wrapping of `Float` methods as functions

The `Float` trait methods will be usable as functions via UFCS, and
we came to a consensus to remove duplicate functions like this a long
time ago.

It does still make sense to keep the duplicate functions when the trait
methods are static, unless the decision to leave out the in-scope trait
name resolution for static methods changes.
std: Switch field privacy as necessary
collections: Switch field privacy as necessary
getopts: Switch field privacy as necessary
native: Switch field privacy as necessary
rand: Switch field privacy as necessary
sync: Switch field privacy as necessary