Added custom-template in examples, as a base template to integrate easily other JS widgets.
Added custom example (based on custom-template project) that demonstrates how to integrate a thirdparty JS component such as d3 within the application using wsf_js_widget.

Removed various unecessary ecf dependencies.
Merge pull request #139 from jocelyn/widget_integration

Added custom-template in examples, as a base template to integrate easily other JS widgets.