add a command to generate proxy template
Support optional and named arguments in constructors.
Add @jsify annotation.
Support automatically proxying Lists and Maps to Dart in Proxies.
Support copying List and Maps to JS in Proxies.
@jsify support for exported member return values.
fix #155: Add @JsName() to specify the JS name of a class member
Fix type annotations in JsList
Update README.md to clarify proxy definition, talk about @jsify, and cover initialization.
Remove 0.4.0 branch reference from README
Merge pull request #174 from a14n/issue-155

fix #155: Add @JsName() to specify the JS name of a class member
Fix example in README
Merge branch 'master' of https://github.com/dart-lang/js-interop
Merge pull request #169 from a14n/create-proxies-command

add a command to generate proxy template
allow JsObject in toDart/toJs