Merge: nitweb: add misc features

A little of everything in this PR:

* show all properties of a class: http://nitweb.moz-code.org/class/core::Array (see all props tab)
* show code into linearization card: http://nitweb.moz-code.org/class/core::Array (see linearization tab)
* show class definitions for modules: http://nitweb.moz-code.org/module/core::array

Pull-Request: #2172
Reviewed-by: Jean Privat <jean@pryen.org>