Update homepage
fix core-ajax-dart and add test
update pubspec and changelog
Merge pull request #108 from dart-lang/fix-core-ajax

Fix core ajax content-type header.
add factory for element wrappers
support transitive base classes that are native dom elements
read all summaries first and collect them, then pass that through when generating the classes
change elements in FileSummary back to just a list
use Element.tag with typeExtension argument
extend from the correct class