Document using parserDefaultArgs to auto-quote `this` parameters

[galenbwill]

Is this a general concept that needs to be documented or a specific API?
This is a specific usage of a feature in Settings that should be documented in the user docs.

What concept or API needs more documentation?
By adding the following to the analysis.types.parserDefaultArgs setting, it is possible to have the clang type parser automagically escape a this parameter when parsing a type string:

-Dthis=`this`

Are there any known examples of people using this API/concept?
This came from a discussion on the pubslack:

[psifertex]

We do already:

https://dev-docs.binary.ninja/guide/types/cpp.html#defining-the-base-classes:~:text=this%20is%20a,the%20type%20parser.

Suggestions welcome for making it more obvious, but closing for now.