[Feature]: Make use of UML4NET

[antoineatstariongroup]

What type of issue is this?

• Bug report
• Feature request

Prerequisites

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• I have verified that I am running the latest version of the X-Splinter
• I have searched open and closed issues to ensure it has not already been reported

Description

Currently, we are using standard XML reader/Writer to read/write the XMI content.

When uml4net will provide all functionalities to write XMI including the extension part, the project has to be refactored to use uml4net read/write features.

Steps to Reproduce

System Configuration

• X-Splinter version:
• Environment (Operating system, version and so on):
• .NET version:
• Additional information: