remove some print statements
[test] small tweaks
[presentation] fixes missing code
[action] reformat code, improve async support
[node] allow node handler to return a tuple
[test] fix tests
fix duplication page rendering
[wkhtmltopdf] add support for wkhtmltopdf
[doc] some update
[wkhtmltopdf] fix rst
[formatter] migrate code to this plugin
[profiler] initial port of WDT from Symfony2