Script input format (context, args) is not documented

[Fayti1703]

Problem

The script function arguments are not documented on the wiki; which is vital information for starting weavers.

Context

There is a forum post with some details on the Context object already, which could be ported over to the wiki as a starting point.

For the Arguments object, I think we should just doc "no args means null" and how scriptors look -- everything else is obviously rather free-form

[Fayti1703]

I will point out that searching for existing issues regarding the Context object is made a lot harder by the fact most issues have a "Context" header, which matches a search for "context".

So if there's already an issue filed for this, that is why I didn't catch it.