[Feature]: Separate TextualNotation to another library #226

What type of issue is this?

• Bug report
• Feature request

Prerequisites

• I have written a descriptive issue title
• I have verified that I am running the latest version of the SysML2.NET
• I have searched open and closed issues to ensure it has not already been reported

Description

The TextualNotation has to be part of a separate library since it is a way to serialize the abstract syntax into a concrete one.

A new project (with its test project) has to be create with the Name : SysML2.NET.Serializer.TextualNotation

Steps to Reproduce

System Configuration

• SysML2.NET version:
• Environment (Operating system, version and so on):
• .NET Framework version:
• Additional information: