Overhaul of advanced features

Origin of:

- composite types
- one of type
- entity definition
- exclusive properties
- examples folder

Syntax update for:

- one of type
- referencing
- templates properties (variable property name)
> If we are doing both, we definitely need to seperate the parts in the Specification.

Both. Note the README.md isn't the specification. It is a mere print of the current syntax. You are correct that full concise specification should look different. I hope this is something our technical writer can do later one from this documents, examples and my additional comments.