fix #728 Headers should not be shared between request handler instances

JSONRequestHandler used to have a headers which were implicitly static,
causing issues when modifying those headers with
RequestHandler#getHeaders().
fix #727 Callback failure when submitting a JSON request should be handled in the framework.

Close #731
refactor Rename some tests

Also fix a minor issue with MaximizableDialogTest which had template test
env set incorrectly.

Close #684.
fix #722 PageEngine animation CSS rules are added multiple times in the DOM
refactor TemplateInheritanceTest

Close #719.
WIP: at-noder-converter + eclipse formatting only
WIP: noder-js
samples: adding a sample