Binding to properties

Bindings are now as properties to improve the help(api) output.
It required to do some changes to bind_api function too. In the same time, I worked to improve the docstrings and transformed some arguments to explicit ones.
A script has been added too to test the urls given as reference of bindings. I don't think it should at the root of the project but didn't know where to put it actually.

Tell me