Update for language changes

-   `loop;` -> `continue;`
-   `#[feature(globs, macro_rules)];`
-   `debug!` now uses `format!`
-   `ch.to_u32()` now returns `Option<u32>`
merged and adjusted gen_index.py for language changes.
enabled Travis CI for Rust nightly.
updated .travis.yml to limit the automated build to nightly branch.
Merge remote-tracking branch 'origin/master' into rust-0.9-pre
Merge branch 'master' into rust-0.9-pre
Merge branch 'master' into rust-0.9-pre
language updates: str.chars(), do requires procs.
Merge branch 'decode-BOM' into decode-BOM-0.9, …

… and remove the back-ported .starts_with() method. It’s in libstd now.
Merge branch 'master' of github.com:lifthrasiir/rust-encoding into rust-0.9-pre
Merge branch 'decode-BOM-0.9' of github.com:SimonSapin/rust-encoding into rust-0.9-pre
language update: no more 'self.
language update: #[link] -> #[crate_id].
Upgrade to latest Rust.
Merge pull request #28 from metajack/rustup-20131219

Workaround rust compiler bug.
updated a link to Travis.
updated .travis.yml.

well, I think this commit should also present to the master
in addition to the rust-0.10-pre branch since Travis always
looks for the most recently pushed commit regardless of the branch.
okay, I should have used rust-0.10-pre branch for image, clarified the branch infos.
we are now tracking rustc master (thanks to unofficial nightlies).
fixed a lifetime problem in tests; updated .travis.yml for automatic documentation generation.