Correct the fallibility of proxy operations in the *Methods trait (fixes #3041).

A typo caused us to use the fallibility of the last normal method in the
interface.
Parallelize test runs on Travis (fixes #2980).
Merge pull request #3015 from Ms2ger/travis-matrix

Parallelize test runs (fixes #2980); r=Manishearth+SimonSapin+metajack
Merge pull request #3057 from Ms2ger/3041-method-trait

Correct the fallibility of proxy operations in the *Methods trait (fixes #3041); r=jdm
Change documenation repository URL back to doc.servo.org

The earlier change got lost in the rebase for #3015
Fix getElementsByTagName[NS] support to match the spec.
Merge pull request #2938 from jgraham/jgraham/getElementsByTagName

Fix getElementsByTagName[NS] support to match the spec; r=Ms2ger
Remove unused windows/globals
Decouple compositing and script crates.
Merge pull request #3054 from jdm/script_traits

Decouple compositing and script crates.
Upgrade Rust.
Merge pull request #3040 from servo/rustup-20140804

Upgrade Rust.
Merge pull request #3060 from Manishearth/remove-window

Remove unused windows/globals; r=jdm
Rename ClientRect and ClientRectList to DOMRect and DOMRectList (fixes #2814, fixes #2840).

These interfaces were renamed in the specification, in order to use them in
other contexts than the getClientRects and getBoundingClientRect methods.