Make DOMString an alias for Option<~str>

Fixes #898.
Replace our rust_box with std::unstable::raw::Box

This will keep us in sync with compiler changes.  In fact we had the 'prev' and
'next' fields in the wrong order (but we aren't using them).
Add support for clearTimeout.
bindings: Return errors in Result rather than setting an out parameter

Fixes #909.
auto merge of #954 : jgraham/servo/clear_timeout, r=metajack
auto merge of #955 : kmcallister/servo/bindings, r=metajack
Move test JS into HTML files

Fixes #896.
Fix some missing end-of-file newlines
use spawn_with in lieu of cells
auto merge of #958 : tikue/servo/master, r=pcwalton

Cells are generally less readable, and spawn_with makes many of them unnecessary.
auto merge of #957 : kmcallister/servo/inline-js, r=jdm
Rename the element field of the DOM Node hierarchy

Renamed htmlelement, and element

Fixes #924
Rename the node field of the DOM node hierarchy

Renamed the Node elements

Fixes #924
auto merge of #959 : luisbg/servo/master, r=jdm

Issue #924
Start pulling together summit demo elements
auto merge of #963 : larsbergstrom/servo/summit, r=jdm

We need to figure out what we need to implement/fix for the summit, and this page pulls together all of the elements we want to show.
Implement document.getElementById().