Stirling PDF Common Module

[DarioGii]

Description of Changes

Introducing the new common module to house common beans, classes and configuration properties that will be used across Stirling PDF. It will also alleviate issues around cross/circular dependencies between modules.

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Checklist

General

• [x] I have read the Contribution Guidelines
• [x] I have read the Stirling-PDF Developer Guide (if applicable)
• [x] I have read the How to add new languages to Stirling-PDF (if applicable)
• [x] I have performed a self-review of my own code
• [x] My changes generate no new warnings

Testing (if applicable)

• [x] I have tested my changes locally. Refer to the Testing Guide for more details.