Move generated tarballs under target/package

At the same time this commit renames the `.tar.gz` extension to `.crate`. This
helps our perception on Windows as we're not trying to leave them out in the
dark, and we'd also like the ability to modify the format later in the future.

Closes #777
Fix infinite recursion when invoked without args
TcpListener::bind now takes 1 argument instead of 2
update rust-encoding

https://github.com/alexcrichton/toml-rs/pull/28 also needs to be in here to truly fix the build
Add 'did you mean...' message when a subcommand is not found.
Merge branch 'fix-build-auth-test.rs' of https://github.com/pwoolcoc/cargo into update
Merge branch 'add-did-you-mean' of https://github.com/pwoolcoc/cargo into update
Merge branch 'args' of https://github.com/ebfe/cargo into update
Fix a tidy issue with src/bin/cargo.rs
Pass `-C prefer-dynamic` for dylib dependencies
Update with breaking changes from tonight's nigthly
auto merge of #811 : alexcrichton/cargo/update, r=alexcrichton

Need to land them all as one unit to actually pass the whole test suite.
auto merge of #798 : alexcrichton/cargo/issue-777, r=brson

At the same time this commit renames the `.tar.gz` extension to `.crate`. This
helps our perception on Windows as we're not trying to leave them out in the
dark, and we'd also like the ability to modify the format later in the future.

Closes #777