Improve the abstract syntax of ini files.

[rfechner]

Main problems include:

• it bugs me, that there is no real way of communicating things like when to do new lines in the esl language.
• Maybe i should switch the language the abstract syntax is written in to XML or possibly yaml-like language.
• The spacial order of things should NOT be to complicated, after all, this abstract syntax is just a shortcut i take because i dont want to create a new language with an interpreter , soundness check and so on.
• Increase readability of the abstract syntax! current language is too technical
• Allow for new features to be added in the future, allow for expressions for filtering.
• Maybe a way better way of describing the format in which i want to have the ini file is a tutorial-like notebook with pictures.
• Should the layer-weight be a metadeclaration? i dont think so..

[rfechner]

I think the simplest way of declaring an abstract syntax will be the BNF https://de.wikipedia.org/wiki/Backus-Naur-Form Should build upon the ini abstract syntax.