Add new Error types
Removing const on RegExp.
Testing for Error instead of old exceptions.
Merge pull request #45 from financeCoding/code_cleanup_sdk_rev14939

Code cleanup in preparation for sdk rev14939
Changes to update to latest sdk - r15013

BUG=

Review URL: https://chromiumcodereview.appspot.com//11412041
API improvements to match dart:html

In particular, fixes #33 (Element.elements) and fixes #36 (rename .span)

These changes are starting to lay the groundwork for:
https://github.com/dart-lang/dart-web-components/issues/107

Review URL: https://chromiumcodereview.appspot.com//11413048
switch to hosted dependency

Review URL: https://chromiumcodereview.appspot.com//11299281
Changes for next sdk release

Review URL: https://chromiumcodereview.appspot.com//11547021
Fix html5lib for the next sdk push.

Review URL: https://chromiumcodereview.appspot.com//11776005
ignore out dir
Merge pull request #51 from kevmoo/ignore_out

ignore out dir
Convert html5lib to use lib v2

Review URL: https://chromiumcodereview.appspot.com//11828059
Optimize .length and .last on ListProxy
(also first/single, but that's less important)

Review URL: https://chromiumcodereview.appspot.com//12025011
remove warning in html5lib.

Review URL: https://chromiumcodereview.appspot.com//12046003
Spelling error in dom.dart

Tiny
Merge pull request #54 from kevmoo/patch-1

Spelling error in dom.dart
Prep html5lib for next sdk release

Review URL: https://chromiumcodereview.appspot.com//12079008
Remove type warning by letting compiler know collection is a List
Renamed Node.elements -> Node.children

Following updates in dart:html
Renamed outerHTML -> outerHtml, innerHTML -> innerHtml

following updates in dart:html
Moved id from Node to Element